Thirty Years War (1618–1648)

Major Figures

Albrecht von Wallenstein

Albrecht von Wallenstein (1583–1634) was an enigmatic and ambitious aristocrat who earned fame as an Imperial general during the Thirty Years War.

Early Years and Education

Born in Bohemia, Wallenstein came from a protestant family that was nobility, but not wealthy nobility. He attended the Jesuit college at Olmütz, and after 1599 he pursued his education at the University of Altdorf and then at Bologna and Padua. Although he was not a distinguished student, astrology caught his attention, and it was a pursuit he followed throughout his life.

He toured Europe and joined the army of Emperor Rudolf II in Hungary, winning honors for his conduct at the siege of Gran in 1604. In 1606 he converted to Catholicism, although his conviction for authority remained stronger than his religious enthusiasm.

In 1609, Wallenstein returned to Bohemia and married a wealthy widow, inheriting her Moravian estates when she died in 1614. He deployed his wealth to earn favor, offering and commanding two hundred horses for Archduke Ferdinand of Styria at the siege of Gradisca during the Archduke’s war with Venice in 1617.

The Conflict Begins

Upon the outbreak of the Thirty Years War, Wallenstein rebuffed the propositions of the Bohemian rebels, instead leaving his estates there and moving with his funds to Vienna to raise a cuirassier (horse soldiers who wore a cuirass, which was a piece of armor protecting the chest and back) regiment. He won distinction fighting and in the wake of the Protestant defeat at White Mountain received large estates for his service from the emperor.

As was characteristic of his nature, Wallenstein exploited the uncertain political situation to his advantage. He regained his Bohemian estates, as well as confiscated Protestant lands. In 1622, further military success earned him rank as imperial count palatine, with more titles to follow. In 1623, he married Isabella Katharina, daughter of Count Harrach, a confidential adviser of the emperor, and was made a prince. Having consolidated vast tracts, he was allowed to form them into a territory named Friedland. Soon thereafter, Albrecht von Wallenstein became Duke of Friedland.

When Ferdinand found few forces at hand to continue prosecuting the war, he turned to Wallenstein, who offered to raise an army in the emperor’s service. Because of his popularity, recruiting proceeded quickly. In 1626, Wallenstein defeated Ernst von Manfeld at Dassau Bridge. Subsequently he campaigned to secure Silesia and to force Denmark from the war. As compensation for his contributions, he was made Duke (later Prince) of Sagan. In 1628 he was granted the duchy of Mecklenburg.

The Political Backlash Gains Strength

Although he was unable to subdue Stralsund (a city on the Baltic whose port offered income from trade with the Scandinavian countries as well as the promise of developing naval power), Wallenstein’s ambitious grasp was attracting resentment from higher-born nobility of the Empire. He frequently behaved independently and took efficient measures to extract plunder from his holdings.

Ferdinand listened to the complaints of his advisors, but he was hesitant to let go of someone who had provided so much to the Imperial cause. Nonetheless, Wallenstein’s many centers of authority were too threatening to ignore. Ferdinand finally determined that Wallenstein’s reach needed to be curtailed, so in September 1630 he sent envoys to announce his dismissal. Wallenstein yielded his army to General Tilly and retired to his duchy of Friedland.

The Swedes Arrive

Wallenstein’s retirement did not last very long. Swedish General Gustavus Adolphus invaded Germany, winning a decisive Swedish victory over Tilly at the Battle of Breitenfeld in 1631. The Swedish advance into southern Germany prompted the Emperor to recall Wallenstein in the spring of 1632. In response, Wallenstein rapidly raised a new army and opened an aggressive campaign. He expelled a Saxon force from Bohemia and in November fought the Swedes at the Battle of Lützen. In this contest Wallenstein was forced to withdraw, but Adolphus was killed.

During the next year, Wallenstein showed a reluctance to engage in decisive battle, instead entering into negotiations to abandon the Imperial cause and defect to his former enemies. Confident that his officers would remain loyal to him, Wallenstein retired to winter quarters in Bohemia. Meanwhile, the Emperor became aware of Wallenstein’s treachery and engineered his removal by a patent of high treason published in Prague on February 18, 1634. Wallenstein fled, but was murdered on February 25, probably by an official loyal to the Emperor.

Wallenstein’s career as a general, like his character, must be considered to be one of ambiguity. He was resourceful and effective with a penchant for grand projects, yet he was also personally harsh, fond of the pleasures of wealth, and secretive. He could inspire others to follow him and engendered lasting loyalty among his officers and subordinates.

While not a great strategist, he competently led his forces on campaign and did not shy from seeking battle when he believed it to his advantage. Wallenstein took as much pleasure in the administration of his extensive estates as he did with military affairs. He sought to improve the operation of his holdings and was willing to compromise religious convictions in the name of statecraft. He believed most of all in himself and in his ability to influence situations for his own benefit, a characteristic that ultimately led to his downfall.

Gustavus Adolphus

Gustavus Adolphus (1594–1632) was King of Sweden from 1611 to 1632. Known as the “Lion of the North,” Gustavus Adolphus transformed military theory and practice. Although he did not bring about an end to the Thirty Years War, his modernized Swedish army changed the face of armed conflict in Europe.

The Prince Becomes King

Adolphus began his career as a reformer and leader at an early age. He received a formal, rigorous academic education, studying Latin and Greek classics, history, theology, and law. He was bilingual in Swedish and German and eventually could converse in other European tongues as well.

While scholarly, Adolphus was no stranger to a battlefield. He saw military action in the Danish War at age sixteen, and he succeeded his father as king on October 30, 1611. This period was a time of trial for Sweden, for political dissension prevailed throughout the Baltic and within Sweden itself. Warfare with neighboring states seemed endemic; Sweden’s small, inadequately trained and equipped army was poorly suited to engage its enemies.

As king, Gustavus inherited no less than three wars with his neighbors (Denmark, Russia, and Poland). He first turned his attention to the nearest and most threatening opponent, Denmark. Competing sovereignty claims and Danish resentment of Swedish independence had prompted conflict that Gustavus now sought to conclude by initiating raids against Danish positions.

His attempts achieved little, and by summer he was forced to parry strong Danish offensive thrusts. Realizing that he could not prevail, he concluded a peace with Christian IV in 1614, a settlement more advantageous to Denmark than to Sweden.

From 1613 to 1617, Gustavus fought Russia, where a clash of territorial and economic interests led to hostilities. Difficult campaigns under harsh conditions ensued, but by 1617 Gustavus’s gains were sufficient to negotiate the Treaty of Stolbova. This ended favorably for Sweden, as they gained control of the Gulf of Finland and cut off Russia from the Baltic.

Competition with Poland prompted the King to lead an offensive in 1617 that he exploited in 1621 with the seizure of the important port and city of Riga. Further campaigns ensued but Gustavus had made his point that Sweden would not be denied. By 1629 Polish forces were largely defeated. With the Treaty of Altmark, Sweden gained further territory, Prussian ports, northern Livonia, and advantageous economic rights.

Battles Abroad, Reforms at Home

Adolphus understood that a vigorous domestic political and economic foundation was necessary if Sweden was to become a major European power. He oversaw the increased development of natural resources, instituted novel manufacturing techniques, expanded trade, and reformed the government’s fiscal structures.

Gustavus achieved his most significant reforms in terms of military affairs. During the sixteenth century in Europe, military practice languished. Dominating infantry combat was the Spanish tercio formation, which combined pikemen and arquebusiers in squares composed of fifteen hundred to three thousand men arranged in a primarily defensive formation. Cavalry formations lacked the offensive capability to attack. Horsemen largely restricted themselves to charging, firing their wheel-lock pistols, and then retiring (a tactic called the “caracole”). Artillery was heavy and difficult to position on the battlefield. Gustavus sought to change this static climate.

Gustavus returned a dynamic flexibility to warfare by building upon a number of the changes already set in motion by the great Dutch reformer Maurice of Nassau. For example, Adolphus restored the infantry’s capacity for offensive action by emphasizing a linear brigade formation. Muskets were located on the flanks and were integrated in the center with pikes, allowing each arm to be more fully employed throughout an engagement. This also facilitated command and control, meaning leaders could more easily direct their units on the battlefield.

Gustavus’s cavalry attacked in three ranks, firing their pistols once but then resorting to sabers for close combat. In terms of artillery, he lightened the weight and size so that cannons could be maneuvered in combat. Also, the use of barrage fires and rolling salvos meant that the artillery was again an active participant in the outcome of fighting. Finally, Gustavus imposed order to his camps and reformed logistical systems to ensure that pay, food, clothing, and training drastically improved.

The Improved Army Heads South

After he had secured peace with Poland, Gustavus entered the Thirty Years War by invading Germany in July 1630. After a brief winter campaign, he assaulted Frankfurt an der Oder and skirmished with the Imperial General Tilly’s forces. When Tilly’s army sacked the city of Magdeburg, which had declared support for Gustavus, the King resolved to bring Tilly to battle.

On September 17, 1631, Gustavus decisively defeated Tilly at the Battle of Breitenfeld, showcasing the Swedish army’s various reforms. Nonetheless, many of Tilly’s men escaped, and the Imperial army soon regrouped. Gustavus next moved toward the Rhine, and in the spring of 1632 he turned eastward. Even though he crossed the Danube, he was unable to bring his Imperial adversaries to battle.

The Emperor now brought Wallenstein to oppose the Swedes, and moving northward, he parried with Gustavus. The Swedish King attacked on November 16 at the Battle of Lützen, and while forcing Wallenstein to retreat, Gustavus was killed.

Was the New Army Not So New?

Revisionist historians assert that Gustavus’s contributions are overstated. They point to the fact that native Swedes frequently constituted a minority of his army. Since the Swedish king could rarely fill his formations to strength, Swedish armies were similar to the mercenary forces fielded by other states. Critics also declare that because his battlefield victories did not bring an end to the Thirty Years War, his military reforms were not substantial; Gustavus was simply carrying through with earlier Spanish and Dutch advances.

Yet what cannot be denied is that Gustavus changed the face of warfare in his lifetime. At the time of his birth, the conduct of war appeared much as it had for a century prior: cumbersome infantry forces slugged it out while largely ineffective cavalry and artillery arms contributed little to the main engagements. By the time Gustavus was killed, all the major powers were emulating his reforms. His campaigns during the Thirty Years War restored mobility to land forces, demonstrated the effectiveness of combined arms, resurrected shock action for the cavalry, maximized the firepower of the artillery, and enabled generals to maneuver ever-larger armies on longer campaigns. For this, Gustavus still stands in the first rank of great leaders.

Lennart Torstensson

An extraordinary artillery officer, Lennart Torstensson (1603–1651) was a leading proponent for advances in early modern artillery doctrine and tactics. His work with the Swedish army helped transform that unit into Europe’s most sophisticated fighting force.

A Soldier’s Life

Precocious as a youth, Torstensson became a page to Gustavus Adolphus as an adolescent. Showing potential as a soldier and leader, he was sent to the Netherlands from 1624 to 1626 to study military affairs under the leading theorist of the period, Maurice of Nassau. Upon his return, Torstensson served under Gustavus in the Prussian and Polish campaigns of 1627–1629. His abilities were rewarded with command of the six companies of the Swedish army’s artillery regiment in 1629.

Torstensson immediately set about training his crews to emphasize mobility and firepower. He insisted that they be ready to deliver a striking blow in concert with the other arms in battle. Torstensson’s artillery played a central role at the Battle of Breitenfeld on September 17, 1631, Gustavus Adolphus’s greatest victory. The Swedish batteries outmaneuvered and dominated the Imperialist cannon, providing the winning margin during the battle’s final attacks. In honor of his achievements, Torstensson was promoted to the rank of general.

In April 1632, his artillery covered the Swedes’ crossing of the Lech, confusing Tilly’s forces and preventing an Imperial assault. Torstensson fought in the attack upon Wallenstein’s encamped army at Alte Veste on September 3–4, 1632, but was captured and held prisoner for a year at Ingolstadt. When he was exchanged, he returned to Sweden and married Baroness Beata de la Gardie.

Once More Into the Thirty Years War

Torstensson became chief of staff to the Swedish general Johan Banér, and between 1635 and 1641 he campaigned with Banér in eastern Germany, rendering important service at the Battle of Wittstock (October 4, 1636). Torstensson later assumed an independent command, although operating jointly with Banér. Torstensson’s insistence that his field artillery be moved around the battlefield and kept firing in positions to aid his infantry became a hallmark of his offensives.

In the wake of the campaign of 1640, Torstensson fell ill and again returned to Sweden. There he was made a senator and promoted to field marshal on August 31, 1641. On his next campaign, he invaded Saxony and besieged Leipzig, assaulting and nearly annihilating the Imperial army during the Second Battle of Breitenfeld (November 2, 1642).

By now known for leading rapid, slashing marches against his opponents, in 1643 Torstensson invaded Moravia again, but he had to return north at the outbreak of war between Sweden and Denmark. He checked Danish advances and attacked as far as Holstein. However, a decade of constant war had robbed his army of many veterans, and his native Swedish regiments lacked their former swagger.

Torstensson soon set off once more for Germany at the head of his army. In early November 1644 he entered Bohemia, and when he scored a win at the Battle of Jankau (March 6, 1645), Vienna appeared to be vulnerable. Nonetheless, his army was exhausted and he was unable to capitalize on the moment. In the aftermath, the toll of many years in the saddle on campaign finally came due, and Torstensson resigned his command and returned to Sweden.

Life after the Military

In 1647 he was made Count Torstensson of Ortola and became governor-general of the western provinces of Sweden. He died at Stockholm on April 7, 1651, and was buried with state honors at Riddarholm Church. Torstensson is remembered as a trusted lieutenant of Gustavus Adolphus; an aggressive artillery general who applied a rational, scientific approach to the employment of indirect fires; and a hero of Sweden.

Vicomte de Turenne

Henri de la Tour d’Auvergne, Vicomte de Turenne (1611–1675), would earn fame as a brilliant operational and tactical leader. One of France’s most popular and famous generals, his military actions helped bring the Thirty Years War to an end.

An Aristocratic Childhood

Born into a noble protestant family, Turenne’s father was a learned aristocrat who maintained close relationships with members of the French court. Turenne’s mother was Elizabeth of Nassau, a capable and headstrong daughter of the Dutch royal line. Over the course of his life, Turenne would become involved in numerous dynastic, religious, and political intrigues among the leading families of France.

As a child, Turenne was sickly, and he fared poorly at his academic lessons. However, he was fond of classical military history and thus studied past martial glories. He became stronger as he grew older, and as an adolescent his mother sent him to her brother, Prince Maurice of Nassau, the greatest military theoretician and reformer of his age. Entering service as a soldier in the Prince’s bodyguard, Turenne quickly demonstrated potential.

Early Military Action

Turenne soon earned a captaincy and took an active role in the siege of Bois-le-Duc in 1629. He returned to French service the following year, where he took command of an infantry regiment and began a period of service in Piedmont and Lorraine. Turenne earned honors for his leadership during the assault at the siege of La Mothe in 1634. For his bravery he was promoted to maréchal de camp, equivalent to the rank of major-general.

In 1635 Turenne campaigned along the Rhine, lifting the siege of Mainz in August, but he was forced to retire due to logistical constraints. With France now having entered the Thirty Years War and fighting against the Habsburgs, Turenne’s prowess as a commander in the field continued to mature, and he became an increasingly important French leader. In 1637 he took a leading role in the army’s actions in Flanders. The next year, in concert with Bernhard of Saxe-Weimar, he coordinated the siege of the Rhine fortress of Breisach, compelling its capitulation in mid-December.

Under the Duke of Harcourt, Turenne next fought in the Italian campaign of 1639–1640 at Casale and Turin, where he suffered a serious wound. He was promoted to lieutenant general, and his fortune continued to ascend. Even though his elder brother was found to be involved in the conspiracy of Cinq-Mars in 1642, the French Minister Mazarin made Turenne Marshal of France in late 1643. Mazarin sent Turenne to Germany to reorganize and train Bernhard of Saxe-Weimar’s troops who had been defeated at Tuttlingen in November 1643.

The Final Chapter of the Thirty Years War Begins

Turenne crossed the Rhine with the advent of warm weather in the spring of 1644. Allied with the great Condé (Louis II de Bourbon, Prince de Condé), the two leaders waged a stiff fight against Bavarian General Franz von Mercy’s forces in August 1644 at Freiburg. There, Turenne’s promotion of a slashing, flanking attack provided the margin of victory.

In 1645, Turenne again opened a campaign across the Rhine, this time with a new army. He confronted Mercy in Franconia once more, but at Mergentheim on May 2 he was outmaneuvered and forced to retreat to Hesse. On August 3, Turenne exacted his revenge at Allerheim (near Nordlingen); the Bavarian host was defeated, and Mercy himself was killed.

In 1646, Turenne joined with Swedish forces under General Gustav Karl Wrangel near Giessen and opened a campaign in Bavaria. These actions resulted in the Truce of Ulm with the Bavarian Elector, Maximilian I, on March 14, 1647.

Facing a mutiny amongst the Weimar troops, Turenne turned his attention to suppressing this revolt with minimal loss of life before once again invading Bavaria, which had returned to active hostilities on behalf of the Habsburgs. The May 17 victory at Zusmarshausen brought an active end to the campaign.

Strife Within the Homeland

The great families of France now became involved in the internal conflict of the Fronde, a rebellion against centralized royal authority. (This revolt was organized by some of France’s leading aristocrats while the young French king, Louis XIV, was still a minor.) Initially, Turenne fled to Holland, where Condé’s sister, Madame de Longueville, persuaded him to join the revolt.

The Treaty of Rueil in March 1649 put an end to the first war of the Fronde, and the second war began with the arrest of Condé and his associates in January 1650. Turenne escaped and engaged in minor actions, but conflict ended by negotiation with the royalist parties still in power and the arrested nobles released. Turenne reconciled himself to the royals and returned to Paris in May 1651. Soon thereafter, Condé again raised a revolt in the south of France. This time, Turenne would oppose his former colleague.

In the third (or Spanish) war of the Fronde, Turenne played a prominent role. He defeated Condé at Gien on April 7, 1652, and nearly ended the war at Porte de St. Antoine (St. Denis), in the Paris suburbs, in early July. In 1653 and 1654, Turenne was occupied with campaigns against the Spanish. He defeated the Spaniards at Arras in the summer of 1654 and continued to advance, capturing numerous towns through 1655, but he suffered a setback when Condé vanquished him at Valenciennes in July 1656. Final victory came on June 14, 1658 at the Battle of the Dunes near Dunkirk. The Treaty of the Pyrenees was signed on November 7, 1659.

Later Wars

Upon consolidating his power, Louis XIV promoted Turenne to marshal-general, giving him authority over all other French marshals. Turenne campaigned actively in Flanders during the War of Devolution in 1667–1668, although Louis’ personal attention to military operations often hindered the field marshal.

In the Dutch War of 1672, Turenne advanced with the king through the United Provinces but was thwarted when the dikes were opened. Turenne next led his army across the Rhine, outmaneuvering the army of the Italian Montecuccoli and Frederick William of Branderburg; this forced the latter out of the anti-French alliance.

Driven back across the Rhine in the fall of 1673, Turenne and his army recrossed in the spring, and in June 1674 he won the Battle of Sinsheim, opening the Palatinate to French arms and deprivations. Turenne next maneuvered to seize Strasbourg on September 24, 1674. Executing a daring winter campaign, he screened his forces with the Vosges range and surprised his enemies at Mulhouse on December 29, 1674, and again at Turckheim on January 5, 1675, thereby securing Alsace.

Turenne was struck and killed by a cannonball during the opening stage of a Battle at Sasbach on July 27, 1675. His remains were buried at St. Denis, the sacred burial grounds of French monarchs. Later, Napoleon would move them to the Invalides, in Paris.

At the Right Place and Time

Turenne’s genius was uniquely suited for the style of warfare of the late seventeenth century. Unafraid of battle, he demonstrated personal courage, tactical ferocity, and a willingness to strike boldly when the opportunity presented itself. Furthermore, he favored operational maneuver and sought to force his enemies into untenable positions from which their only choice was to yield or to surrender a key piece of terrain.

Given the increasingly expensive, technically trained and professional armies of the era, Turenne’s sophisticated, economical approach to warfare was just what the monarchs he served wanted from their leaders in the field.

Major Battles

White Mountain, November 8, 1620

Won by the Catholic-Imperial side, the Battle of White Mountain was an early contest of the Thirty Years War that served to widen the conflict and firmly established Habsburg rule over the Czech people.

Religious Tolerance Goes out the Window

For years, a fragile balance existed between Protestant and Catholic princes and their subjects within the Holy Roman Empire. This delicate peace was undone in 1617, when Emperor Matthias designated Ferdinand of Styria as his successor. Ferdinand was an ardent Catholic, and although he outwardly promised to uphold the rights of the estates assemblies, the Protestant nobility fully expected him to pursue a strict Catholic ideology.

In May 1618, a group of Protestant nobles entered the palace in Prague and hurled several of Ferdinand’s confidants from the windows into the ditch below. Although the ejected men survived, this “Defenestration of Prague” set in motion events that culminated in the outbreak of the Thirty Years War in Europe.

A general Protestant uprising in Bohemia and Hungary ensued, threatening Habsburg interests throughout the Empire. This unrest stretched even as far as the Low Countries, where allies might be attained with the restless Dutch who were actively fighting the Spanish Habsburgs.

In June 1619, a general assembly of the estates of the lands of the Bohemian Crown offered Frederick V of the Palatinate a crown to stand as rival king to Ferdinand. As a Calvinist married to the daughter of King James of England, Frederick came to the forefront as a leader with significant Protestant credentials, and he could be expected to draw substantial European support.

Start the Revolution Without Us

Frederick arrived in Prague in October amidst much diplomatic activity, but he was disappointed to find little direct assistance proffered by fellow Protestant leaders. James, despite his daughter’s direct involvement, faced a reluctant aristocracy in London that was tired of continental adventures and wary of Dutch plans. The Dutch offered a few thousand men and a modest subsidy only, as they already had their hands full contesting Imperial forces nearer to home. German Lutherans sensed that Frederick would be defeated and were unwilling to oppose the Emperor.

The Habsburgs moved to suppress the rebellion on several fronts. A Spanish fleet was dispatched to Flanders, and Spanish general Spinola captured Frederick’s lands on the left bank of the Rhine in the summer of 1620. Fearful of Spanish ambitions, Maximilian of Bavaria offered his Catholic League forces to Ferdinand.

In July 1620, Maximilian’s army—about thirty thousand strong and commanded by the experienced Count von Tilly—marched into Austria. This compelled the Austrian Estates to abandon their alliance with the Bohemian rebels. Frederick’s commander, Christian Anhalt, was left to face the Imperialists alone.

The Battle of White Mountain

Maneuvering in the vicinity of Prague in November, the opposing armies drew near and prepared for battle. Anhalt deployed his army along the crest of a hill, presumptuously named White Mountain (Bílá Hora in Czech), astride the road to Prague. His army’s position was defensible, with one flank anchored near a hunting lodge that provided a degree of cover, while his other flank rested on a minor stream. Soft ground covered much of the low-lying areas at the bottom of the slopes.

Nonetheless, Anhalt’s men were poorly trained, lightly armed, and lacking a unifying élan. Tilly’s army, on the other hand, contained more veterans and was organized for combat. After just a few hours fighting, Anhalt’s men began streaming to the rear, with the center of his position broken.

Frederick V, thereafter known as the “Winter King,” fled into an exile that lasted for the remainder of his life, dying in Mainz in 1632. His Bohemian rebels met a likewise harsh fate. Confident in the wake of his forces’ victory, Ferdinand II exploited his advantage to political and personal gain. He mandated extensive transfers of property from rebel landholders, disrupting the broader economy and diminishing the value of Czech currency, but enriching his Catholic allies and solidifying their support for the Emperor’s cause.

The Sands Do Not Question Authority

Ferdinand also imposed a severe course of re-Catholicization, declaring, “Better to rule over a desert than a country full of heretics.” Protestant ministers were ordered to depart Bohemia in 1624, and three years later all Bohemian subjects were compelled to choose between exile and Catholicism. Tens of thousands of subjects chose to depart their homeland. Many suffered even more harshly. In June 1621, more than two dozen rebel leaders were executed in Prague’s town square.

While the course of the Thirty Years War would rage across Bohemia and central Europe until 1648, the Czech people would remain firmly within the orbit of Habsburg authority for the next three centuries.

Magdeburg, May 1631

The siege and sack of the Saxon city of Magdeburg by Imperial troops of the Holy Roman Empire under the command of Count Graf Johann Tserclaes von Tilly was one of the most notorious atrocities of the Thirty Years War. The destruction of the city served to galvanize Protestant resistance and symbolized the excesses of the war.

Catholic Ascendancy in the Early Years

In 1624, the Emperor Ferdinand II deposed the leading Protestant noble in Germany (the Elector Frederick V), giving the title to Maximilian of Bavaria. Frederick’s expulsion and the consequent military disarray on the Protestant side left Tilly’s army as the dominant force in northern Germany.

During the years 1625–1629, Protestant hopes were raised by the intervention of the Hague Alliance comprising England, the Netherlands, and Denmark. Once again, though, Catholic arms gained the upper hand, and it seemed the war might be winding down.

But in March 1629, the Emperor ignited Protestant resistance again by his declaration of the Edict of Restitution. Reaching back into the past, the Edict stated that the secularization of church lands was illegal, and that (in effect) only Lutheran Protestantism was permissible. Calvinism and other Protestant faiths were forbidden.

The restoration of Catholic properties and influence was clearly intended to effectively strangle Protestant believers within the Empire. Following the Edict, the Catholic electors reorganized Catholic military forces. In 1630, they compelled the removal of the mercenary general Albrecht von Wallenstein and named Count Tilly as commander of both the Imperial Army and the forces of the Catholic League, the latter numbering about twenty thousand men.

Sweden Enters the Fray

While Protestant fortunes waned during the 1620s, the Swedish commander Gustavus Adolphus was waging a lengthy war in Poland; hence, he did not contest the armies of the Emperor. Prompted in part by the Edict and partially by the desire to expand Swedish influence, Gustavus launched an invasion of central Europe in July, 1630.

The Swedish army soon occupied Stettin, capital of Pomerania. After securing his base, Gustavus planned an active campaign for the spring of 1631. However, before his army could make any substantial gains, Tilly besieged Magdeburg, which had declared allegiance to the Swedes and had resisted the re-Catholicization program mandated by the Edict.

Tilly was an experienced professional who had campaigned since the 1580s in the Low Countries. He had likewise been fighting since the opening years of the Thirty Years War. It was his army that confronted the Bohemian rebels under Frederick at the Battle of White Mountain, and he had inflicted the defeat that sent Frederick and the Protestant cause into retreat.

In March 1631, Tilly moved his army before the city’s defenses and began a deliberate siege, reinforcing the troops of his field marshal Pappenheim who had started siege operations the previous November. Tilly counted slightly more than twenty thousand soldiers. This was not a large force, but it still overwhelmed the small Swedish force garrisoning the city, which was led by the Swedish colonel Diedrich von Falkenburg.

Realizing the seriousness of the situation at Magdeburg, Falkenburg appealed to Gustavus for relief. Recognizing that the appearance of Gustavus’s army would force him to lift the siege and offer battle, Tilly ordered an assault on May 20. After a sharp fight lasting only a few hours and during which von Falkenburg was killed, Tilly’s men seized the city.

A City Ravaged

While it was customary for occupants of a city that had resisted a siege to suffer at the hands of a victorious attacking force, the rampage of the Imperial troops at Magdeburg went far beyond contemporary conventions. In an orgy of destruction, Tilly’s men proceeded to burn most of the dwellings and slaughter the city’s men, women, and children. Only approximately five thousand of the city’s thirty thousand inhabitants survived. Protestant broadsheets describing the terror of the pillage circulated widely throughout Europe and served to galvanize Protestant determination to continue the war.

Following the sack, revenge became a new motivation for an already lengthy and bloody conflict. Gustavus took his measure when he inflicted a significant defeat upon Tilly’s army at the Battle of Breitenfeld in September. Still fighting the Swedes, Tilly was mortally wounded and died in April 1632. Magdeburg did not recover for many years—by the mid-1630s, only a handful of families resided there.

First Breitenfeld, September 17, 1631

A critical contest of the Thirty Years War, the First Battle of Breitenfeld checked Habsburg momentum by turning back Imperial armies from northern Europe and reviving Protestant fortunes. The battle also marked the ascendancy of Gustavus Adolphus and his novel system of warfare that sought to provide commanders with the means to bring crushing firepower to bear on the battlefield.

The Swedes Modernize

As the opening battles of the Thirty Years War raged across central Europe during the 1620s, Gustavus Adolphus was aggressively organizing, training, and equipping a new kind of army. His aim was to restore flexibility to land combat by capitalizing upon the reforms initiated by the great Dutch theoretician Maurice of Nassau. Under Gustavus’s tutelage, Swedish infantry adopted a linear, brigade formation that maximized both firepower and maneuverability. The cavalry advanced in three ranks, firing their pistols when closing, but then resorting to sabers for close combat. The weight of Swedish artillery was lessened so that the guns could be repositioned during action, allowing commanders the ability to concentrate fires at the decisive time and place on the battlefield. And Gustavus built cohesive formations by ensuring that the soldiers were paid and fed, and that order was imposed in camp and on the march. This combination of efforts created an army that was fundamentally distinct from other fighting forces.

With a truce in hand with Poland, and seeking to check the Habsburgs on the continent, Gustavus invaded Germany in the summer of 1630 and spent much of the year consolidating his base and reinforcing his army. In the spring of 1631, the Swedes took to the field, but Gustavus could not bring the main Imperial host, under Count Tilly, to battle. In September, now augmented by the men brought by John George of Saxony, Gustavus pressed Tilly, who fell back upon Leipzig. Gustavus’s army numbered about 42,000 while Tilly commanded approximately 35,000.

The Imperials Find the Swedes

On September 16, Count Pappenheim, Tilly’s cavalry commander, encountered a detachment of Swedes. Pappenheim sent word back to Tilly that he was engaged and requested support. Tilly marched from Leipzig, selecting advantageous terrain near the village of Breitenfeld. Aligning his army along a slight rise, he placed more than a dozen tercios in his army’s center, with cavalry covering each wing and artillery at center front.

Shortly after dawn on September 17, Gustavus brought his army forward. Unbothered by Tilly’s static formations, he assembled in a parallel line about a half mile distant. John George’s Saxons claimed a spot to the Swedes’ left, with their infantry in groups of one thousand men each, shaped into a pyramid-like formation. Gustavus’s Swedes reflected their new, linear-style organization. Artillery covered the infantry in the center with cavalry on the flanks in the traditional manner. However, instead of a single line, the Swedish formations arranged themselves in depth, so that the brigades nearest the enemy were mutually supporting. Furthermore, several artillery pieces were located with each brigade, and cavalry appeared in small numbers amidst the infantry. Overall, Gustavus had achieved a combined-arms posture that would allow infantry, cavalry, and artillery to fight simultaneously.

About midday, the battle opened with a conventional barrage. Each side suffered, but the Swedes could fire faster than Tilly’s cannoneers. Unwilling to bear any more casualties, Pappenheim charged the Swedish right. Musket fire and cannonades from the embedded infantry and guns shredded the Imperialists. Pappenheim would not be denied and ordered charge after charge, each with the same bloody result. When the Catholics had been repulsed seven times, Gustavus ordered a counterattack with his reserves, scattering Pappenheim’s troopers.

Maneuvers During the Conflict

On the Swedes’ left flank, Imperial hopes were brighter. At the first assault by the Habsburg cavalry there, the Saxons had broken and fled. With one flank in desperate combat but the other victorious, Tilly sensed an opportunity. He ordered his tercios to march obliquely to the right, overlap the Swedish left, and then strike the open flank abandoned by the Saxons.

Yet Gustavus had organized and deployed his army to counter just such a maneuver. Instead of crumbling, the Swedes stiffened their defense. By shifting brigades and rearranging his cannon, Gustavus was able to pressure Tilly’s greater numbers.

At the right moment, Gustavus ordered a counterattack. Tilly’s tercios were by now smashed tightly together and could barely move or fight effectively, while the Imperial cannon remained immobile up the slope. The Swedes savagely assaulted across the front in an irresistible onslaught, destroying Tilly’s army and chasing the remnants from the field.

Morning light revealed about 7,500 dead from Tilly’s army on the field. Another several thousand were killed during the wild retreat, and nearly ten thousand were captured while thousands more deserted. In short, Tilly’s army was grievously wounded and the Imperial cause suffered a severe blow. While he lost about five thousand men, Gustavus clearly demonstrated the superiority of his military reforms in action.

While the First Battle of Breitenfeld did not end the Thirty Years War, it changed the war’s course in favor of the Protestant Alliance. Most importantly, it established Gustavus Adolphus and his Swedish reforms as the model for a European way of war that would dominate during the coming centuries.

Lützen, November 16, 1632

The Battle of Lützen, which pitted the Swedish army of the Great Captain Gustavus Adolphus against the army of the Imperial general Count Albrecht von Wallenstein, was a central event of the Thirty Years War. Although a tactical Swedish victory, Gustavus was killed, and Swedish ambitions never recovered from his demise and the battle’s heavy loss of life.

The Swedes Move Through Germany

In the wake of Gustavus’s victory at the Battle of Breitenfeld in September 1631, fresh recruits arrived in number to the camps of his army. He also gained additional support from German princes. Gustavus had a clearly devised strategy for subduing his opponents, and his objective was the destruction of the Emperor Ferdinand’s armies in the field.

As part of this strategy, rather than march to occupy the Habsburg capital city of Vienna, Gustavus led his forces toward the Rhine and then down the Danube. This path served to deny Emperor Ferdinand support from Catholic Bavaria, while allowing Gustavus’s men to gather provisions from the estates of their enemies.

By December 1631, Gustavus had occupied the Rhineland and forced the Spanish garrisons to retire back to the Netherlands. After wintering in the Main valley, Gustavus set off in the spring of 1632 with a host numbering more than 120,000 men (only a minority of this host were native Swedes). Adolphus crossed the Danube and brushed aside the Imperialist army gathered by Count von Tilly, his foe from Breitenfeld. When word reached the Swedish lines that Tilly himself had been killed, it seemed that the war might be soon over.

A Desperate Emperor Makes a Desperate Move

Worried about defeat, Ferdinand reached out to Count von Wallenstein, the mercenary and ambitious general whom he had already removed due to Wallenstein’s hunger for power. Wallenstein was wary of fighting Gustavus in a set-piece battle, so he first struck at the Swede’s Protestant ally John George. In short order, Wallenstein attacked George and drove his Saxons back into Bohemia. Gustavus marched north to confront Wallenstein, but neither side wanted to risk battle on anything other than favorable terms. For weeks, stalemate persisted until, in early September, Gustavus feinted in the direction of Vienna.

Wallenstein, a wily military leader himself, did not take the bait, and instead headed farther north into Saxony. Gustavus returned on Wallenstein’s heels, but by now it was November. Wallenstein therefore entered winter quarters, assuming the campaign season was concluded for the year. Wallenstein even sent his formidable cavalry general, Pappenheim, away on another mission.

Gustavus, however, wanted a battle and prepared a surprise attack. By chance, his assault was uncovered by a small detachment of Imperial cavalry. Hence, each army, now aware of the others’ proximity, hastily prepared for battle.

Battle Formations

The terrain near the village of Lützen was fairly level, with the most prominent feature being the ditched road running northeasterly to Leipzig. Wallenstein positioned his main line north of the road and placed musketeers at the road’s edge. He tied his left flank into a shallow river, while his right rested on the edge of the village. In conventional fashion, four large tercios occupied the Imperial center, with artillery directly to their front on a slight rise. Cavalry guarded both flanks.

Gustavus deployed his army in two lines, thereby ensuring that his eight infantry brigades in the center were directly supported. The Swedish army continued to reflect the many reforms Gustavus had accomplished since the 1620s. Contingents of infantry were posted with the cavalry on each flank, and the Swedish artillery was lighter and hence more maneuverable than that of the Imperialist host. The Swedes’ plan was to strike Wallenstein’s left and then roll up the cumbersome tercios which would be unable to turn and meet the onrushing Swedish troops. Gustavus’s force numbered about nineteen thousand, while Wallenstein totaled slightly less.

The Battle is Joined

Led by Gustavus, the Swedish right successfully broke Wallenstein’s army and began turning on the stiffening Imperial defenses. On his other flank and in the center, the Swedish army was making only slow progress. As Gustavus rode across the line to inspire his left, Pappenheim returned to the battlefield. Wallenstein immediately ordered him to attach the Swedish right, and when he did, the Swedes were completely surprised.

Confusion reigned as the battle became a swirling mass of horses and men, with smoke and fog obscuring the action. At that moment, Pappenheim was struck and killed by a cannonball, prompting the Imperial horse to panic. Wallenstein, who could not see this development, thought he had turned the tide and hence ordered a counterattack all along the line of the road. Gustavus, rallying his men, was then cut down, initially giving pause to the Swedish army. Then, in a fit of rage, the Swedes assaulted to avenge their leader, driving Wallenstein’s men from the field.

Wallenstein withdrew to Leipzig, but the Swedish army was too devastated to offer effective pursuit. Each side lost between three thousand and five thousand dead and wounded, with several thousand more missing. More importantly, the Swedish army never fully recovered from the loss of so many veteran leaders, especially their king, Gustavus. This campaign would lead to French involvement and the expansion of the war.

Rocroi, May 19, 1643

The Battle of Rocroi opened the final chapter of the Thirty Years War. Most significantly, it marked the end of Spanish military domination in Western Europe. Subsequently, French arms and French military leaders would come to dominate European battlefields for the next century.

Combat Fatigue

By the early 1640s, Europe had been at war for more than two decades and all parties were suffering from economic and social exhaustion. However, none of the major belligerents was yet willing to yield territory or make concessions without compensation for their protracted exertions.

France had stood on the sidelines as long as possible, but with the demise of Gustavus Adolphus and the subsequent defeat of the Swedish army at Nördlingen in 1634, French interests were now threatened. As Imperial armies gained the upper hand in Germany, and with Spanish forces occupying the western bank of the Rhine, Cardinal Richelieu (the French Prime Minister) considered the strategic situation too perilous to ignore. Hence, he led France into active conflict by opening another front against Spain in the Low Countries.

Leading French arms in the field was Condé, Louis II de Bourbon Duc d’Enghien, only twenty-two years old at the time of Rocroi. A noble by birth, Enghien received a Jesuit education before going to Paris in 1637 to study military affairs. Richelieu identified him as a young man of great promise; Enghien participated in the siege of the port of Fuentarrabia, and he volunteered to take part in the siege of Arras in 1640. Shortly before his death, Richelieu designated Enghien as commander of the northeastern armies.

The Spanish Enter France

When a Spanish Imperial army more than 25,000 strong under Francisco de Melo advanced from the Netherlands through the Ardennes toward Paris, Enghien moved to confront the invader. He initially established a defensive position along the Meuse River, but fearful that the Spanish would be reinforced, he soon abandoned this line. After Melo halted to lay siege to the town of Rocroi, Enghien felt that he must attack at once with his 23,000 men.

Against the advice of his more experienced advisors, Enghien led his army on a difficult approach through heavily wooded defiles that Melo had failed to obstruct. Arriving near Rocroi late in the afternoon of May 18, the French army took up positions along a ridge south and east of the city. The Spanish responded by immediately moving from their works to confront Enghien’s men. Both sides then spent the night in their positions.

Formations at Rocroi

Melo deployed his infantry with the traditional tercios in the center of his line. Spanish troops comprised the first line nearest the French, and they were supported by less dependable Italian and German soldiers in a second line. Some three thousand cavalrymen protected the Spanish right, while another five thousand took their place on the left.

Enghien’s army aligned itself in virtually the same formation: infantry in the center, guns forward, cavalry on each flank, and a cavalry reserve in the rear. However, the French army was organized into linear brigades that offered their commander a great deal of flexibility and increased the force’s frontal firepower.

Rocroi Begins with Cavalry

Shortly after sunrise, Enghien personally opened the battle by leading a successful cavalry charge that ruptured the Spanish left. Splitting his successful squadrons, he ordered some to pursue the fleeing enemy horsemen, while he turned into the waiting Spanish infantry with the remainder. Eager to enter the fight, Enghien’s cavalry on his opposite flank also attacked, but these were thrown back and sent reeling in disarray. Only the French cavalry reserve was able to stop the surging Spanish horse.

Even with this setback, Enghien was an audacious commander, and he was determined to carry the day. When Enghien learned of the peril on his left, he led the cavalry still with him directly through the center rear of the Spanish tercios, cutting and slashing his way to assault the remaining Spanish cavalrymen. He finally scattered them and left the heavy Spanish infantry isolated on the field.

After two assaults by his brigades on the Spanish squares failed, Enghien concentrated all his artillery against the Spanish foot and opened a tremendous barrage. Isolated and losing hope that their cavalry would return, the Spanish infantry asked for quarter, a gesture Enghien accepted. However, as he advanced to receive the Spanish surrender, some of the infantry mistook his approach as the signal for yet another French attack and opened fire at his party. Infuriated by this apparent treachery, the French infantry assaulted the withered Spanish formations mercilessly, destroying them where they stood. More than eight thousand of Melo’s men were killed and another seven thousand captured; Enghien’s casualties numbered about four thousand.

Although the Thirty Years War would continue for another five years, Rocroi finally ended the Spanish tercio’s domination of infantry combat in Europe. While Gustavus’s Swedish brigades had demonstrated that they could defeat the tercios, it was not until Rocroi that the Spanish formation was finally shown to be outdated.

For France, the young Enghien would eventually earn the title of the “Great Condé” and enter the first rank of French military leaders.

Second Breitenfeld, November 2, 1643

The Second Battle of Breitenfeld was a Swedish victory in the later years of the Thirty Years War that marked a low point for Imperial prospects. Although the battle did not signal the end of the conflict, the fate of the Emperor was severely threatened by the loss; his forces were saved from further defeat only by the reprieve gained at the onset of war between Denmark and Sweden.

The War Drags On

In the years following the death of the great Swedish field marshal Gustavus Adolphus, the generals he trained—including Johan Banér, Lennart Torstensson, and Karl Gustav Wrangel—continued to lead armies reflecting the Great Captain’s reforms. Swedish forces, although their ranks were increasingly thinned by mercenary troops from other nations, deployed to battle in linear brigades that maximized infantry firepower. Swedish cavalry was aggressive and hard-hitting, charging with pistols and sabers to deliver shock to enemy formations. Importantly, mobile artillery was integrated with the other two arms to ensure that Swedish commanders could employ massed gunfire at the decisive time and place on the battlefield.

Nonetheless, Swedish arms had not brought the war to a conclusion, and though victories were won in many engagements, overall campaigns were not decisive. Over time, this endless cycle of war and encampment began to take a toll on all sides, including the Swedes. When Johan Banér died in May 1641, his army mutinied. Axel Oxenstierna, Chancellor of Sweden, appointed the aggressive Torstensson to restore order and achieve the victory Sweden needed.

In November 1641, Torstensson assumed command and added several thousand new recruits to his army’s ranks. He quickly set about preparing for a fresh campaign. The year prior, a combined offensive by the armies of Sweden, France, and Brunswick had driven as far as the Danube at Regensburg but could advance no farther before being compelled to retire to winter quarters.

Torstensson opened his new campaign by marching into Silesia and defeating the Elector of Saxony’s forces at Schweidnitz. Next he invaded Moravia and occupied its capital, Olmütz, in June 1642. Recognizing the threat posed by this Swedish host, an Imperial army led by Austrian General Octavio Piccolomini and Archduke Leopold-William moved to confront the Swedes. In the face of the Imperial advance, Torstensson retired to Saxony and laid siege to Leipzig.

Breitenfeld, Part II

Outnumbered, Torstensson fell back near Breitenfeld and took up position for battle. His plan for his initial deployment was typical: long brigades of infantry in echelon occupying the center of his line, with cavalry squadrons on both flanks and a small reserve at the middle rear. While both sides were still moving into position, the Imperial artillery opened fire. Rather than assemble under the cannonade, Torstensson launched a hasty attack on his Imperial enemy’s left flank, surprising his opponents and sending the Imperialist horse into headlong flight.

Alerted to the threat posed by the impetuous Swede commander, the Imperialist commanders were faring much better in the middle and on their own right flank. Although the Imperialist army had not adopted the kinds of reforms instituted by the Swedes, their leaders, as well as many of their foot soldiers, were veterans and not easily rattled.

Seeing that his center and left were now in peril, Torstensson led another charge, wheeling into the flank of the Imperialist infantry to provide enough space for his own struggling footmen to regain their formations and counterattack. Finally pressed hard by the Swedes, the Imperialist troops remaining on the field broke and ran or surrendered.

The Imperialists counted about five thousand killed and five thousand captured, while the Swedish losses amounted to approximately two thousand killed and two thousand seriously wounded. Torstensson completed his victory by capturing Leipzig the following month. He and his forces were diverted to attack Denmark thereafter, and the Thirty Years War continued.

Zusmarshausen, May 17, 1648

Fought near Augsburg, the Battle of Zusmarshausen was the final battle of the Thirty Years War. The defeat of the Imperial forces by a Swedish-led army and the siege of Prague finally compelled Emperor Ferdinand to enter into conclusive negotiations. This led to the Congress of Westphalia, which brought the war to an end.

The Long Stalemate

The performance of each sides’ armies leading up to Zusmarshausen gave little indication that the end of fighting was near, as neither side could gain a decisive advantage. Even the one significant diplomatic development, which held promise for a change of course in the war, ultimately proved barren. By the Treaty of Ulm (signed in March 1647), Maximilian of Bavaria turned away from his alliance with Ferdinand III and withdrew from the war. Although the peace would only last several months, during the interlude French and Swedish armies possessed an opportunity to press the Empire.

However, during the summer the Dutch war effort against Spain slackened, allowing the Spanish to move a larger number of forces southward to the borderlands of France. This repositioning successfully diverted French attention, as Mazarin ordered Turenne to move his forces into Luxembourg and northern France to repel the Spanish incursions. Compounding French problems, the Weimarian troops refused to advance beyond Germany, compelling Turenne to put down their revolt before moving on.

In the end, the Spanish offensives against France from the Low Countries turned into nothing more than another round of sieges and ineffectual maneuvering. The French proved they could do little better; they were repulsed in several places and had to withdraw upon the approach of Imperial forces.

Different Country, Same Outcome

In the German lands, Swedish general Karl Gustav Wrangel attacked through Bohemia but was stopped in his tracks by the Imperial commander Peter Melander. As so often occurred at this late stage of the war, the need to find fresh sources of supply from the war-ravaged countryside effectively restricted the ability of commanders to maneuver their forces. Faced with limited logistical means that were always inadequate in any case, the Swedes gradually marched northward. The Imperialists, not seeking battle, were glad to see them go; instead of pursuing, they marched into Hesse to settle other disputes with the local nobility.

In the fall, the Treaty of Pilsen brought Bavaria back into the war on the side of Emperor Ferdinand III. The Bavarian army consequently marched into the Upper Palatinate to join Imperial troops in Bohemia. Wrangel retired through Saxony and Hesse as Turenne returned to Germany to again combine with the Swedes, although little more was achieved before the onset of another winter.

A New Year Brings a Change

Departing quarters in the spring of 1648, the French and Swedish forces of Turenne and Wrangel opened the new campaign by pushing back the Imperialists and Bavarians to the line of the Danube. After maneuvering independently for a period near Nördlingen, the French and Swedes pressed forward, trapping the Imperialists at Zusmarshausen. The Imperial rearguard was routed, its commander Peter Melander becoming a casualty. While this sharp fight was not large, it was a defeat the Imperialists could ill afford.

The Imperial and Bavarian remnants fell back to the River Inn before general Octavio Piccolomini—called by the Emperor to restore order—was able to check Turenne and Wrangel’s advance. Piccolomini hurriedly reorganized what remained of the Austro-Bavarian army, and checked his enemies from making any further progress.

While events in Bavaria were turning against the Empire, another Swedish army had entered Bohemia and was besieging Prague. This new threat prompted Ferdinand to demand the assistance of Piccolomini’s army, thereby freeing Turenne and Wrangel to pressure Munich. Neither side could make much progress, however, and the campaign devolved into foraging and plundering.

Negotiation for a peace settlement had reached a critical stage, with all sides believing an end was near. The Imperial defeat at Zusmarshausen and the persistence of Swedish and French armies in the heart of Germany was the final straw. Before Prague could be assaulted or any further offensives organized in Germany, word arrived to the armies that a peace accord had been reached. Finally, three decades of warfare came to a conclusion.

Key Elements of Warcraft

Standing Armies

The Thirty Years War (1618–1648) occurred during a centuries-long period of military transformation that witnessed a nearly ten-fold increase in the size of armies. Starting in the early sixteenth century, the manner in which officials raised, equipped, and deployed armies underwent significant change. Military and political leaders wrestled with emerging ideas of military organization, technology, and strategy as they waged war throughout Europe. During the three decades of the Thirty Years War, the identity and operation of government became increasingly tied to the ability to manage violence through permanently organized and increasingly large armed forces, resulting in changes to the administration of states as well as to broader military culture.

A European Arms Race

In the late fifteenth century, the Spanish monarchy employed only about twenty thousand men in the army and navy; by the 1630s, Spain was funding 300,000. France supported perhaps forty thousand soldiers in 1500 but counted 400,000 two centuries later. Other nations followed a similar path. By the early eighteenth century, the Dutch and Swedes each boasted about 100,000 men in their armed forces, and England had nearly that many.

While most generals found it difficult to muster more than twenty thousand or thirty thousand fighting men for any single battle, the overall number of men in the field of all arms (infantry, cavalry, and artillery) was much greater. Even though the need to gather food for horses and men alike did limit the size of the force on campaign at any one time, military leaders learned to conduct rapid marches and soldiers were always adept at compelling residents to divulge their local stores.

As armies grew, so did the costs to sustain them. While states differed administratively, every monarchy found it necessary to dispatch commissioners to extract payments and subsidies to supplement income derived from hereditary lands and properties. Loans, either voluntary or under various degrees of duress, were also sought. The Imperial Armies alone may have cost as much as 250 million gulden during the war, the vast majority of this expense being borne by the Emperor.

Consequences of the Military Expansions

The integration of military power with the development of states now appears to historians to have been so substantial in its effects that the concept of a military revolution has been thoroughly incorporated into the canon of early modern European history. The historiographical debate has turned to the precise nature and timing of military change in early modern Europe.

The military revolution that occurred in sixteenth- and seventeenth-century Europe sprang from the tactical reforms undertaken by Maurice of Nassau and Gustavus Adolphus—most notably a return to linear formations for short-armed infantry and limited, if aggressive, charges by cavalry. As the relative importance of cavalry declined, the significance of massed infantry, with their projectile-firing muskets, increased dramatically. Larger, infantry-centric armies thus became typical.

Weapons Bring Changes As Well

Nonetheless, the initial surge in military manpower across Europe began before Maurice’s reforms. Changes in siege warfare also prompted calls for larger armies. Castle and town walls designed to resist bombardment by medieval siege engines quickly succumbed to gunfire, so the masonry walls that had been the standard form of fortification throughout the Middle Ages no longer offered protection.

Improvements in gun-founding and the manufacture of gunpowder increased the effectiveness of cannons as instruments of destruction. The result was the erection of new fortifications consisting of earthworks faced with brick or stone. These were designed to achieve a low profile to offer the smallest possible target to an attacker’s guns. The superb ability of this type of fortress, known as the trace italienne, to resist both bombardment and infantry assault tipped the strategic balance in favor of the defensive. Siege warfare, with its attendant entrenchments, artillery, and mining equipment, required manpower on an unprecedented scale. Hence, successful states were those that organized themselves by amassing military power.

Even as the Thirty Years War ravaged many areas within central Europe, the continent as a whole experienced economic and population expansion over the sixteenth and seventeenth centuries. The growing population and wealth of Europe are also key factors contributing to governments’ willingness and ability to deploy larger standing armies.

What is clear is that the sustainment of armies was inextricably tied with the growing complexity of government. The centrally organized, bureaucratically governed nation-state—the paramount symbol of the modern era—that emerged from the simple beginning of late sixteenth-century tactical reforms matured on the battlefields of the Thirty Years War to play a key, even a pre-eminent, role in shaping the modern world.

Impact on World History

The Thirty Years War was a multifaceted, dynamically shifting, European-wide conflict. The war began largely due to a religious dispute between German Roman Catholics and Protestants, but the contest quickly became ensnared in the dynastic competition for power within the Holy Roman Empire. The war also developed into a political conflict that pitted the ambitions of the Catholic Austrian rulers, and later Spanish Habsburg rulers, against the Protestant leaders of Denmark and Sweden, and then even against Catholic France. Throughout the conflict, the German states aligned themselves according to the fortunes of war and the calculations of their princes.

Over the many years of fighting, the war developed a momentum of its own that became difficult to arrest. Ultimately the Thirty Years War was not decided by a single battle or even campaign. Even though exhaustion began to set in on all sides, no one power could bring the hostilities to an end. Governments had expended so much treasure and blood that leaders were reluctant to settle unless they could present specific advantages to their populaces and recoup their own investments in the war effort.

For generations, the horrors of the war’s depredations haunted Europeans’ collective memory. While not all of Europe suffered, and not all of Germany was plundered, the Holy Roman Empire was subject to almost continuous warfare between 1618 and 1648, causing terrible losses in life and property. A precise accounting is difficult, but German population increased over the last half of the sixteenth century but declined between 1600 (15 million) and 1650 (11 million). Tax records indicate that the number of “deserted places” grew significantly as villagers fled the approach of invading armies or simply could no longer earn an income from their devastated properties. Swedish forces alone destroyed about two thousand castles, over fifteen thousand villages, and more than a thousand towns. The most notable atrocity of the war occurred in the city of Magdeburg, which was sacked by the Imperial General Tilly in 1631. It was reduced from a population of more than twenty thousand people to only 394 households in 1635. Across the war zones, plague, famine, and failed harvest followed the armies.

Although the social order composed of corporations, orders, and kinship and patronage ties proved resilient—long-lasting populist or peasant revolutions did not occur—European society was transformed. The war banished the idea and ambition for a unified Christendom modeled after the glory of the long-vanished Roman Empire. The power of the papacy was permanently reduced; thereafter, governments depended overwhelmingly upon their secular leaders for decisions and authority in all its forms. Fiscal, diplomatic, judicial, and military power became increasingly the province of a single, centralized, and secular authority.

In addition, just as the armies of the Thirty Years War ignored their confessional loyalties to wage war alongside their ideological opponents, after 1648 confessional political alliances began fading. Mercantilist economic theory demanded that ideological uniformity be superseded by economic interests; lands and territories were viewed as sources of income for the central government, and this aspect was considered more important than religious identification.

The war also accelerated the complex transformation of government and a comprehensive change to the nature of warfare that was already underway in early modern Europe. In this “military revolution” which started in the late sixteenth century and into the first years of the war, military and political leaders wrestled with emerging ideas of military organization, technology, and strategy. Their solutions, which involved the adoption of massed, linear infantry formations and aggressive charges by cavalry supported by mobile artillery, characterized warfare for the next two centuries and required fundamental changes to how states organized, trained, and maintained armies. Likewise, soldiers adapted to new ideas of sustained, rigorous, and technical training that fundamentally changed how they prepared for battle.

Concurrent with the desire to avoid large-scale bloodshed and changes to military doctrine, new kinds of fortifications emerged that rendered Medieval-style castles and siege works obsolete. Earthworks were now faced with brick or stone and designed to achieve a low profile to offer the greatest possible resistance to an attacker’s guns. States began to build complex series of fortresses to guard decisive points and to line frontiers. By the early eighteenth century, war became primarily an affair of sieges and the reduction of fixed fortifications. Siege warfare, with its attendant entrenchments, artillery, and mining equipment, required huge sums of money and manpower on an unprecedented scale, placing still further demands on governments that both reinforced central authority and stretched the capacity of state leaders to respond effectively.

The Peace of Westphalia was an incomplete settlement and did not achieve the general peace its promoters foretold. Within the German lands, social and political tensions, even if they were dampened by exhaustion, remained largely unaddressed. War continued between France and Spain until the Peace of the Pyrenees in 1659. Even then, French ascendance, sometimes attributed as a product of Westphalia, was not assured. It would take English assistance in the years soon after 1648 and then decades of campaigning by Louis XIV’s generals before France finally emerged as triumphant over at least the Spanish Habsburgs.

Yet despite its short-term ambiguities, the Thirty Years War continues to matter to modern history. The settlements of 1648, while incomplete in many respects, marked a signpost to the future of Europe and ultimately the international state system still functioning today. New ways of war, the alignment of states according to balance of power and economic interests, and the growth of European political identities founded upon modern notions of statehood are each contained within the tumultuous years from 1618 to 1648.

Robinson, J.H., ed. Readings in European History. Boston: Ginn, 1906.