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Missouri Compromise

Missouri Compromise

The Missouri Compromise of 1820 was a congressional agreement that regulated the extension of slavery in the United States for thirty years. Under the agreement, the territory of Missouri was admitted as a slave state, the territory of Maine was admitted as a free state, and the boundaries of slavery were limited to the same latitude as the southern boundary of Missouri, 36°30′ north latitude.

By 1818 the rapid growth in population in the North had left the Southern states, for the first time, with less than 45 percent of the seats in the U.S. House of Representatives. The U.S. Senate was evenly balanced between eleven slave and eleven free states. Therefore, Missouri's 1818 application for statehood, if approved, would give the slave states a majority in the Senate and reduce the Northern majority in the House.

In 1819 the free territory of Maine applied for statehood. Speaker of the House henry clay of Kentucky saw this event as an opportunity to maintain the balance of free and slave states. He made it clear to Northern representatives that Maine would not be admitted without an agreement to admit Missouri. Clay persuaded opponents of slavery to drop efforts to ban it in the territories. In return, the Southern states agreed to limit slavery to the territory below 36°30′ north latitude. Under this provision the unsettled portions of the louisiana purchase north and west of Missouri would be free from slavery. The only area remaining for further expansion of slavery would be the territory that would become Arkansas and Oklahoma. To preserve the sectional equality in the Senate, Missouri and Maine were to be admitted to the Union simultaneously. Clay managed to pass the compromise in the House by a three-vote margin.

In 1821 Missouri complicated matters, however, by inserting a provision into its state constitution that prohibited free blacks and mulattoes from entering the state. Northern representatives objected to this language and refused to give final approval for statehood until it was removed. Clay then negotiated a second compromise that removed the offensive language from the Missouri constitution and substituted a provision that prohibited Missouri from discriminating against citizens from other states. Left unsettled was the question of who was a citizen. With this change Missouri and Maine were admitted to the Union.

Source: Statutes at Large, vol. 6 (1822), pp. 545–548, 645; Ben Perley Poore, ed., The Federal and State Constitutions, Colonial Charters, and Other Organic Laws of the United States, vol. 2 (1878), pp. 1107–1108.

Missouri Compromise

An Act to Authorize the People of the Missouri Territory to Form a Constitution and State Government, and for the Admission of Such State into the Union on an Equal Footing with the Original States, and to Prohibit Slavery in Certain Territories


Be it enacted by the Senate and House of Representatives of the United States of America, in Congress assembled, that the inhabitants of that portion of the Missouri territory included within the boundaries hereinafter designated, be, and they are hereby, authorized to form for themselves a constitution and state government and to assume such name as they shall deem proper; and the said state, when formed, shall be admitted into the Union, upon an equal footing with the original states, in all respects whatsoever.


And be it further enacted, that the said state shall consist of all the territory included within the following boundaries, to wit: beginning in the middle of the Mississippi River, on the parallel of thirty-six degrees of north latitude; thence west, along that parallel of latitude, to the St. Francis River; thence up, and following the course of that river, in the middle of the main channel thereof, to the parallel of latitude of thirty-six degrees and thirty minutes; thence west, along the same, to a point where the said parallel is intersected by a meridian line passing through the middle of the mouth of the Kansas River, where the same empties into the Missouri River, thence, from the point aforesaid north, along the said meridian line, to the intersection of the parallel of latitude which passes through the rapids of the river Des Moines, making the said line to correspond with the Indian boundary line; thence east, from the point of intersection last aforesaid, along the said parallel of latitude, to the middle of the channel of the main fork of the said river Des Moines; thence down and along the middle of the main channel of the said river Des Moines, to the mouth of the same, where it empties into the Mississippi River; thence, due east, to the middle of the main channel of the Mississippi River; thence down, and following the course of the Mississippi River, in the middle of the main channel thereof, to the place of beginning: provided, the said state shall ratify the boundaries aforesaid. And provided also, that the said state shall have concurrent jurisdiction on the river Mississippi and every other river bordering on the said state, so far as the said rivers shall form a common boundary to the said state; and any other state or states, now or hereafter to be formed and bounded by the same, such rivers to be common to both; and that the river Mississippi and the navigable rivers and waters leading into the same shall be common highways, and forever free, as well to the inhabitants of the said state as to other citizens of the United States, without any tax, duty, impost, or toll, therefore, imposed by the said state.


And be it further enacted, that all free white male citizens of the United States, who shall have arrived at the age of twenty-one years, and have resided in said territory three months previous to the day of election, and all other persons qualified to vote for representatives to the general assembly of the said territory, shall be qualified to be elected, and they are hereby qualified and authorized to vote, and choose representatives to form a convention, who shall be apportioned amongst the several counties as follows:

From the county of Howard, five representatives. From the county of Cooper, three representatives. From the county of Montgomery, two representatives. From the county of Pike, one representative. From the county of Lincoln, one representative. From the county of St. Charles, three representatives. From the county of Franklin, one representative. From the county of St. Louis, eight representatives. From the county of Jefferson, one representative. From the county of Washington, three representatives. From the county of St. Genevieve, four representatives. From the county of Madison, one representative. From the county of Cape Girardeau, five representatives. From the county of New Madrid, two representatives. From the county of Wayne, and that portion of the county of Lawrence which falls within the boundaries herein designated, one representative.

And the election for the representatives aforesaid shall be holden on the first Monday and two succeeding days of May next, throughout the several counties aforesaid in the said territory, and shall be, in every respect, held and conducted in the same manner and under the same regulations as is prescribed by the laws of the said territory regulating elections therein for members of the general assembly, except that the returns of the election in that portion of Lawrence County included in the boundaries aforesaid shall be made to the county of Wayne, as is provided in other cases under the laws of said territory.


And be it further enacted, that the members of the convention thus duly elected, shall be, and they are hereby authorized to meet at the seat of government of said territory on the second Monday of the month of June next; and the said convention, when so assembled, shall have power and authority to adjourn to any other place in the said territory, which to them shall seem best for the convenient transaction of their business; and which convention, when so met, shall first determine by a majority of the whole number elected, whether it be, or be not, expedient at that time to form a constitution and state government for the people within the said territory, as included within the boundaries above designated; and if it be deemed expedient, the convention shall be, and hereby is, authorized to form a constitution and state government; or, if it be deemed more expedient, the said convention shall provide by ordinance for electing representatives to form a constitution or frame of government; which said representatives shall be chosen in such manner, and in such proportion as they shall designate; and shall meet at such time and place as shall be prescribed by the said ordinance; and shall then form for the people of said territory, within the boundaries aforesaid, a constitution and state government: provided, that the same, whenever formed, shall be republican and not repugnant to the Constitution of the United States; and that the legislature of said state shall never interfere with the primary disposal of the soil by the United States, nor with any regulations Congress may find necessary for securing the title in such soil to the bona fide purchasers; and that no tax shall be imposed on lands the property of the United States; and in no case shall nonresident proprietors be taxed higher than residents.


And be it further enacted, that until the next general census shall be taken, the said state shall be entitled to one representative in the House of Representatives of the United States.


And be it further enacted, that the following propositions be, and the same are hereby, offered to the convention of the said territory of Missouri, when formed, for their free acceptance or rejection, which, if accepted by the convention, shall be obligatory upon the United States:

1. That section numbered sixteen in every township, and when such section has been sold or otherwise disposed of, other lands equivalent thereto and as contiguous as may be shall be granted to the state for the use of the inhabitants of such township for the use of schools.

2. That all salt springs, not exceeding twelve in number, with six sections of land adjoining to each, shall be granted to the said state for the use of said state, the same to be selected by the legislature of the said state, on or before the first day of January, in the year one thousand eight hundred and twenty-five; and the same, when so selected, to be used under such terms, conditions, and regulations as the legislature of said state shall direct. Provided, that no salt spring, the right whereof now is, or hereafter shall be, confirmed or adjudged to any individual or individuals, shall, by this section, be granted to the said state: and provided also, that the legislature shall never sell or lease the same, at any one time, for a longer period than ten years, without the consent of Congress.

3. That 5 percent of the net proceeds of the sale of lands lying within the said territory or state, and which shall be sold by Congress from and after the first day of January next, after deducting all expenses incident to the same, shall be reserved for making public roads and canals, of which three-fifths shall be applied to those objects within the state, under the direction of the legislature thereof; and the other two-fifths in defraying, under the direction of Congress, the expenses to be incurred in making of a road or roads, canal or canals, leading to the said state.

4. That four entire sections of land be, and the same are hereby, granted to the said state, for the purpose of fixing their seat of government thereon; which said sections shall, under the direction of the legislature of said state, be located, as near as may be, in one body, at any time, in such townships and ranges as the legislature aforesaid may select, on any of the public lands of the United States. Provided, that such locations shall be made prior to the public sale of the lands of the United States surrounding such location.

5. That thirty-six sections, or one entire township, which shall be designated by the president of the United States, together with the other lands heretofore reserved for that purpose, shall be reserved for the use of a seminary of learning, and vested in the legislature of said state, to be appropriated solely to the use of such seminary by the said legislature. Provided, that the five foregoing propositions herein offered, are on the condition that the convention of the said state shall provide by an ordinance, irrevocable without the consent of the United States, that every and each tract of land sold by the United States, from and after the first day of January next, shall remain exempt from any tax laid by order or under the authority of the state, whether for state, county, or township, or any other purpose whatever, for the term of five years from and after the day of sale; and further, that the bounty lands granted, or hereafter to be granted, for military services during the late war shall, while they continue to be held by the patentees or their heirs, remain exempt as aforesaid from taxation for the term of three years from and after the date of the patents, respectively.


And be it further enacted, that in case a constitution and state government shall be formed for the people of the said territory of Missouri, the said convention or representatives, as soon thereafter as may be, shall cause a true and attested copy of such constitution, or frame of state government, as shall be formed or provided, to be transmitted to Congress.


And be it further enacted, that in all that territory ceded by France to the United States under the name of Louisiana, which lies north of thirty-six degrees and thirty minutes north latitude, not included within the limits of the state contemplated by this act, slavery and involuntary servitude, otherwise than in the punishment of crimes whereof the parties shall have been duly convicted, shall be, and is hereby, forever prohibited. Provided always, that any person escaping into the same, from whom labor or service is lawfully claimed in any state or territory of the United States, such fugitive may be lawfully reclaimed and conveyed to the person claiming his or her labor or service as aforesaid.

Approved, March 6, 1820.



The general assembly shall not have power to pass laws—

1. For the emancipation of slaves without the consent of their owners; or without paying them, before such emancipation, a full equivalent for such slaves so emancipated; and,

2. To prevent bona fide immigrants to this state, or actual settlers therein, from bringing from any of the United States, or from any of their territories, such persons as may there be deemed to be slaves, so long as any persons of the same description are allowed to be held as slaves by the laws of this state.

They shall have power to pass laws—

1. To prohibit the introduction into this state of any slaves who may have committed any high crime in any other state or territory;

2. To prohibit the introduction of any slave for the purpose of speculation, or as an article of trade or merchandise;

3. To prohibit the introduction of any slave, or the offspring of any slave, who heretofore may have been, or who hereafter may be, imported from any foreign country into the United States, or any territory thereof, in contravention of any existing statute of the United States; and,

4. To permit the owners of slaves to emancipate them, saving the right of creditors, where the person so emancipating will give security that the slave so emancipated shall not become a public charge.

It shall be their duty, as soon as may be, to pass such laws as may be necessary—

1. To prevent free Negroes and mulattoes from coming to and settling in this state, under any pretext whatsoever; and,

2. To oblige the owners of slaves to treat them with humanity and to abstain from all injuries to them extending to life or limb.


In prosecutions for crimes, slaves shall not be deprived of an impartial trial by jury, and a slave convicted of a capital offense shall suffer the same degree of punishment, and no other, that would be inflicted on a white person for a like offense; and courts of justice, before whom slaves shall be tried, shall assign them counsel for their defense.


Any person who shall maliciously deprive of life or dismember a slave shall suffer such punishment as would be inflicted for the like offense if it were committed on a free white person.



Resolved by the Senate and House of Representatives of the United States of America, in Congress assembled, that Missouri shall be admitted into this Union on an equal footing with the original states in all respects whatever upon the fundamental condition that the fourth clause of the twenty-sixth section of the third article of the constitution submitted on the part of said state to Congress shall never be construed to authorize the passage of any law, and that no law shall be passed in conformity thereto, by which any citizen, of either of the states in this Union, shall be excluded from the enjoyment of any of the privileges and immunities to which such citizen is entitled under the Constitution of the United States. Provided, that the legislature of the said state, by a solemn public act, shall declare the assent of the said state to the said fundamental condition and shall transmit to the president of the United States, on or before the fourth Monday in November next, an authentic copy of the said act; upon the receipt whereof, the president, by proclamation, shall announce the fact; whereupon, and without any further proceeding on the part of Congress, the admission of the said state into this Union shall be considered as complete.

Approved, March 2, 1821.

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Missouri Compromise (1820)

Missouri Compromise (1820)

James L. Huston

Excerpt from the Missouri Compromise

And be it further enacted, That in all that territory ceded by France to the United States, under the name of Louisiana, which lies north of thirty-six degrees and thirty minutes north latitude, not included within the limits of the state, contemplated by this act, slavery and involuntary servitude, otherwise than in the punishment of crimes, where of the parties shall have been duly convicted, shall be, and is hereby, forever prohibited...

In 1819 Congress first confronted the frictions produced by a division of the country into free and slave states. In that year the territory of Missouri sought statehood, and Northern (free) states resisted its admission as a slave state. Northerners, believing the South had too much power already, opposed any expansion of slavery that might strengthen that power. In response to this Northern opposition, legislators came up with the Missouri Compromise of 1820 (10 Stat. 548), as a means to avoid the conflicts raised by territorial expansion.

The compromise set a precedent for states to enter the Union in pairs (one free, one slave). This was not a written part of the law but rather a general understanding among senators to ensure that the number of slave-state senators would equal the number of free-state senators. The compromise also divided the land acquired from France in the Louisiana Purchase into two areas: in the land above 36 degrees 30 minutes north latitude, slavery would be prohibited; in the land below the line, slavery would be permitted. The Missouri Compromise turned out to be a successful one, and after a few years many even viewed it as a part of the Constitution (though it never was). Until the Civil War broke out in April 1861, all attempted solutions to the question of slavery's expansion rested on the Missouri Compromise line of 36 degrees 30 minutes.


By 1819 several Northern congressmen felt aggrieved by the power of the South in national affairs. Southerners dominated national politics through the operation of the Three-Fifths Compromise. Slaves, legally considered a form of property, were allowed to count as three-fifths of a person for the calculation of population to determine the number of congressional representatives a state would have. The Three-Fifths Compromise gave Southerners an edge in electing presidents and constructing majorities in Congress, and through it they managed to dominate the Democratic-Republican party, the party of Thomas Jefferson.

Northerners were also angry at the policies of the two presidents from Virginia, Jefferson (18011809) and James Madison (18091817). Restrictions on trade with Great Britain and France, including an embargo on American shipping in 1808, and the War of 1812 had all hurt the economy of Northern states. To make matters worse, the Federalist Party, which often pushed for policies that benefited the North, bungled its opposition to the war and managed to commit suicide by appearing traitorous.

Meanwhile, Southern slavery was spreading to the Great Lakes area (the present states of Ohio, Michigan, Indiana, Illinois, and Wisconsin), where it had been prohibited by the Northwest Ordinance of 1787. By 1818 it looked as if Southern migrants to Illinois and Indiana were trying to smuggle the "peculiar institution" into those states by calling the practice "indentured servitude" This too provoked the outrage of Northerners.


On February 13, 1819 Representative James Tallmadge, Jr., a Democratic-Republican from New York, offered two amendments to the legislation admitting Missouri to the Union. One called for the prohibition of further importations of slaves into Missouri, and the other demanded gradual emancipation of slaves already there. The House of Representatives passed his two amendments by a sectional vote. In the Senate, where the numbers of slave states and free states were evenly balanced, the amendments were defeated. For the entire year, debate over slavery raged in Congress. This debate amazed the American people, because there was no agitation over the question in any other quarter.

A breakthrough came when the District of Maine, formerly an area controlled by the state of Massachusetts, sought statehood. Speaker of the House Henry Clay (from Kentucky) insisted that if Maine was to be admitted, then Missouri should be admitted as well. Thus the idea of letting states enter the Union in pairs, one free, the other slave, was formally presented. Then Illinois senator Jesse B. Thomas offered an amendment that would establish the line of 36 degrees 30 minutes in the Louisiana Purchase territory, below which slavery was allowed and above which it was not. (The line would approximately form the southern border of the new state of Missouri.) After much dispute between the Senate and the House on final versions of the bill, Congress passed the Missouri Compromise on March 2, 1820.

But the drama was not quite finished. Missourians, angry over Congress's intervention in the question of slavery, rewrote parts of their state constitution denying any free black person the ability to settle in the state. This provision clashed with the guarantee of the U.S. Constitution that citizens in one state would not be discriminated against in another state. So another major collision between Northerners and Southerners followed. The matter was solved by asking Missouri legislators to rewrite the offending section. (Although this was not done, few pursued the matter afterward.) On February 26, 1821, the House of Representatives passed the resolution to admit Missouri to the Union.


Much ill will was generated by the Missouri debates. Southerners did not believe that Northerners harbored any humanitarian concern for slaves. Rather, they believed Northerners merely used the slaves' existence as a way to resurrect the Federalist Party and to create a stronger central government. For Northerners, the debates showed that Southerners did not foresee a future end of slaveryto the contrary, the institution was becoming stronger. And Northerners realized that along with the growth of slavery came Southerners' desires to use national legislation to protect and extend the institution. It was not long after the Missouri debates that the proslavery argument began in earnest. Those in favor of slavery argued that Africans were meant by nature and by God to be slaves and never independent citizens.


Despite the ongoing tension between North and South, the Missouri Compromise handled the national issue of slavery smoothly for several decades. The first part of the compromise was roughly observed until 1850the admission of states in pairs, one free and one slave, balancing the number of senators from each type of state. The admission of slave states ended with the Compromise of 1850, when California was admitted to the Union without an offsetting slave state.

But in many ways, the core of the Missouri Compromise was the line of 36 degrees 30 minutes. Before long, Northerners looked upon this section of the compromise, which "forever prohibited" slavery above it, as holy writ, not to be disturbed. However, it only operated in the Louisiana Purchase area. When the United States gained the territories of California and New Mexico in a war with Mexico, the compromise line again became a source of North-South wrangling. Southerners wanted to extend the line to the Pacific Ocean, but Northerners adamantly refused. When the Compromise of 1850 was written, there was no mention of the 36 degree 30 minute line. Then in 1854 the Kansas Nebraska Act repealed the 36 degree 30 minute line of the Missouri Compromise. This action led to a political explosion in the North, killing the Whig Party and giving birth to the Republican Party. The Republicans insisted that Congress could prohibit slavery in the territories, whereas Southern radicals (called "fireaters") insisted slavery had to be permitted and even protected in all U.S. territorial possessions.

In Dred Scott v. Sanford (1857), the chief justice of the Supreme Court, Roger B. Taney, declared the compromise line unconstitutional and in substance approved the radical Southern position. That case only infuriated the North, and by 1860 the Republicans successfully captured the presidency. In 18601861, in an effort to avoid the division of the nation, Kentucky senator John J. Crittenden used the Compromise Line as part of a general proposal, called the Crittenden resolutions, to reconcile North and South and reunify the country. It was the last public appearance of the compromise line.

The Civil War erupted following the attack on Fort Sumter on April 15, 1861. Congress passed a prohibition of slavery in the territories in June 1862, and with Union victory in 1865, slavery ceased in the United States.

See also: Compromise of 1850; Fugitive Slave Acts; Kansas Nebraska Act of 1854.


Dangerfield, George. The Awakening of American Nationalism, 18151828. New York: Harper and Row, 1965.

Fehrenbacher, Don E. Sectional Crisis and Southern Constitutionalism. Baton Rouge: Louisiana State University Press, 1995.

Knupfer, Peter B. The Union as It Is: Constitutional Unionism and Sectional Compromise, 17871861. Chapel Hill: University of North Carolina Press, 1991.

Miller, John Chester. The Wolf by the Ears: Thomas Jefferson and Slavery. New York: Free Press, 1977.

Moore, Glover. The Missouri Controversy, 18191821. Lexington: University of Kentucky Press, 1966.

Wiecek, William M. The Sources of Antislavery Constitutionalism in America, 17601848. Ithaca, NY: Cornell University Press, 1977.

Louisiana Purchase

Sold to the United States by France in 1803, the Louisiana Purchase was a huge territory stretching from the Mississippi River to the Rocky Mountains and from the Gulf of Mexico to Canada. The property had gone from French rule to Spanish rule and then back again to the French under Napoleon. President Thomas Jefferson believed that control of the West hinged upon possession of New Orleans, at the mouth of the Mississippi. He wrote, "There is on the globe one single spot, the possessor of which is our natural and habitual enemy. It is New Orleans." He secured its control by purchasing the entire territory for $15 million, doubling the size of the United States, in what is now considered one of his greatest achievements.

The Dred Scott Case

Dred Scott was a slave who sued for his freedom in Missouri courts on the basis of having spent nine years in the free state of Illinois and the free territory of Wisconsin. Missouri courts had traditionally upheld the doctrine of "once free, always free," and the case was initially settled in Scott's favor. However, the Missouri Supreme Court stepped in to overturn the decision. The case eventually made its way to the Supreme Court, where each judge rendered a separate opinion. The only aspect of the case the justices agreed upon was that a slave was not a citizen, and therefore was not allowed to sue in federal court. The Court also ruled the Missouri Compromise unconstitutional, finding that the federal government did not have the right to outlaw slavery in the new western territories. Northerners were outraged at the decision, which intensified antagonism between the North and the South, contributed to the election of President Abraham Lincoln, and pushed the country toward civil war. The sons of Scott's first owner, Peter Blow, had helped pay Scott's legal fees during his decade-long legal battle. After the Supreme Court ruled against him, they purchased Scott and his wife and set them free. Scott died nine months later.

Antebellum Period

Alfred L. Brophy

During the antebellum periodthe years before the Civil WarCongress's legislation aimed at continuing to promote economic development, expansion of the Union, and dealing with the conflict over slavery.

In the aftermath of the War of 1812, Congress passed extensive tariff legislation. When South Carolina opposed the tariff act of 1832, Congress passed the Force Bill that authorized Andrew Jackson to use federal troops to enforce the tariff; the nation was on the brink of civil war. War was avoided by a compromise tariff in 1833, yet the nation was well on the road to war. At the same time, Congress was spending money on internal improvements, known as the American System, which provided funding for roads, canals, and railroads. It also passed a bank ruptcy act.

Slavery and settlement of the West were central issues of antebellum politics. In 1820 the Missouri Compromise attempted to settle the conflict by prohibiting slavery in the territories north of Missouri's southern border. Later, the Compromise of 1850, which included the Fugitive Slave Act, again tried to calm the conflict, as did the Kansas Nebraska Act.

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Missouri Compromise


MISSOURI COMPROMISE, legislation enacted by the U.S. Congress in 1820 settling the first serious American sectional crisis over slavery's expansion: the Maine statehood act of 3 March ("An Act for the admission of the state of Maine into the Union") and the Missouri enabling act of 6 March ("An Act to authorize the people of the Missouri territory to form a constitution and state government, and for the admission of such state into the Union on an equal footing with the original states, and to prohibit slavery in certain territories"). The crisis, in conjunction with economic disputes deriving from the panic of 1819, helped to undermine American national unity in the so-called "Era of Good Feelings" following the War of 1812.


The Missouri controversy erupted unexpectedly in 1819, when northern congressmen objected to the Missouri Territory, part of the 1803 Louisiana Purchase from France, being admitted to the Union as a new slave state. Previously, northern congressmen had not obstructed the

admission of new slave states. Later that year, Congress would grant statehood to Alabama by a joint resolution that left its slave labor system intact. However, some northern congressmen took exception to Missouri becoming a slave state, apparently less because slavery was already entrenched in the territory (bonds people were approximately 16 percent of its population) than because Missouri was located directly west of a free state (Illinois) as well as west of the Mississippi River. Their unwillingness to countenance slavery's encroachment northward and westward initiated a struggle that endangered the Union.

The Congressional Impasse

New York Representative James Tallmadge Jr. ignited the dispute on 13 February 1819, when during the Fifteenth Congress's second session he moved an amendment to a House bill permitting the Missouri Territory to take preparatory steps for statehood. Tallmadge's amendment proposed gradually ending slavery in Missouri by prohibiting the "further introduction" of slaves there and by freeing the children of slaves already in Missouri at statehood when those children reached the age of twenty-five. The House, dominated 105 to 80 by representatives from nonslave states (because population growth in the free states had outstripped the growth rate in slave states), twice that session passed the Missouri bill with Tall-madge's amendment. However, in both instances the more southern-oriented Senate demurred. The Senate was far more evenly divided than the House, reflecting the Union's composition at that time of eleven free states and ten slave states, with free Illinois having a system of black apprentice labor that amounted to quasi-slavery. During the same session, southerners also narrowly defeated a northern effort to prohibit slavery in the Arkansas Territory, that part of the Louisiana Purchase territory below Missouri.

Congress again took up the Missouri question in December 1819, when the Sixteenth Congress convened. With Alabama now a state, southerners had even more power in the Senate. Earlier that year, however, the government of Massachusetts had authorized the district of Maine to separate from it and seek statehood (provided that Congress authorize it by 4 March 1820). Maine's admission promised to augment the number of free states in the country and free-state influence in the Senate. Maine's petition for statehood also came before Congress in December 1819. The Missouri and Maine issues ignited the angriest exchanges among national leaders over slavery's morality and its appropriateness in a democratic republic since the U.S. Constitutional Convention. On 26 January 1820, in the midst of predictions of disunion and war, Representative John W. Taylor of New York offered an even more radically antislavery amendment than Tallmadge's to the House enabling bill for Missouri. This proposal, which would have made all children of slaves in the new state free at birth, received the House's endorsement on 25 February. Meanwhile, the Senate considered its own measures respecting Maine and Missouri.

The Compromise

The breakthrough occurred on 2 March, when, following the recommendation of a House-Senate conference committee, the House voted 90 to 87 to delete the Taylor amendment from its Missouri bill and 134 to 42 to substitute for it an amendment to a competing Senate bill that had been offered by Senator Jesse B. Thomas of Illinois. Thomas's amendment, which had passed the Senate by a 34 to 10 vote on 17 February, prohibited slavery throughout the Louisiana Purchase territory, excepting Missouri, north of 36 degrees 30 minutes. On 3 March, the House and Senate concurred in a conference committee report on statehood for Maine. According to the act approved that day, Maine's statehood would occur on 15 March. The Missouri enabling act, with the Thomas amendment embedded within it as section 8, received President James Monroe's signature and became law on 6 March.

The Missouri question was not completely settled, however, until the Sixteenth Congress's second session (which began on 14 November 1820), after Missouri's proposed state constitution came under consideration. Although most of the document was virtually copied from the constitution of Kentucky and thus was unexceptional, the proposed constitution's twenty-sixth section included wording that called upon the new state's assembly to adopt legislation to prevent "free negroes and mulattoes" from entering and residing in Missouri "under any pretext whatsoever." A select Senate committee endorsed Missouri's admission under this constitution, but the controversial provision sparked heated debate in the full Senate not only on race in America but also, again, on slavery. Missouri's stipulation especially raised the issue of whether blacks were or could be U.S. citizens.

The Senate ultimately evaded the issue by passing on 12 December, without a recorded vote, a resolution endorsing Missouri's statehood, with a proviso previously introduced by Senator John Eaton of Tennessee, stipulating that congressional consent should not be construed as endorsing any clause in Missouri's constitution contravening the "privileges and immunities"—or equal citizenship—clause of the federal constitution. Missouri's constitution encountered more resistance in the House of Representatives, which refused to accept the Senate's resolution, not only delaying Missouri's admission but also throwing into question whether Missouri's three electoral votes should be counted on 14 February 1821, when the electoral votes for the 1820 presidential election were totaled by Congress. In a chaotic scene, the president of the Senate announced the results both with and without Missouri's inclusion. That same month, Representative and former speaker Henry Clay played a key role in resolving the imbroglio over Missouri's constitution, by using his influence to get the matter referred to a joint House-Senate committee. The committee then recommended a resolution (subsequently approved) incorporating the substance of Eaton's proviso, with the added stipulation, sometimes designated the Second Missouri Compromise, that Missouri's state legislature confirm in "a solemn public act" that its constitution abided by Eaton's requirement. Although Missouri's subsequent 26 June declaration denied Congress's right to require such a statement, President Monroe proclaimed Missouri's statehood on 10 August 1821.

Significance of the Compromise

Some historians suggest that the Missouri Compromise is a misnomer because majorities of northerners and southerners did not alike endorse all its key elements. In the House vote deleting Taylor's antislavery provision from the Missouri bill, for example, free-state congressmen voted overwhelmingly, 87 to 14, in favor of retaining the constraint. It was only because four free-staters abstained that compromise forces carried the day. Some historians, moreover, have echoed southern charges at the time and interpreted Tallmadge's initiative as an attempt to revive the fortunes of the fading Federalist Party, since some of the most vehement antislavery diatribes in Tall-madge's support came from Federalist congressmen, most notably Senator Rufus King of New York. If the majority Republican Party split along sectional lines, it might pave the way for a Federalist resurgence. But both Tallmadge and King had earlier demonstrated antislavery tendencies, and historians have yet to uncover documents proving that the amendment originated as a partisan cabal.

Historians further disagree over how to interpret the ringing defenses of slavery issued by southern congressmen in the heat of the debates. One can see such rhetoric as evidence that the northern assault on slavery influenced a gradual shift in southern public opinion from conceding that slavery was evil to proclaiming it a positive good, and that it thus backfired by provoking southerners to relinquish an earlier receptivity to slavery's ultimate abolition. However, the breakdown of voting on the Missouri measures also shows that some southerners remained uncertain about slavery's future. For instance, border slave state representatives voted 16 to 2 for Thomas's barrier against slavery's expansion. Further, as William W. Freehling argues in The Road to Disunion, some southerners who endorsed slavery's continued access to the West argued that this would help diffuse the institution into extinction. What historians do agree on is that northern attacks were prompted, in no small measure, by resentment of the political advantage given the slave states by the three-fifths clause in the U.S. Constitution (which allowed slaves to be counted as population for the purposes of political representation but did not allow them to vote), that northerners and southerners alike felt that the sectional balance of power hinged on the outcome of the dispute, and that significant numbers of southern congressmen had reservations about the precedent set by Thomas's limitation on slavery's future expansion. House Virginians voted 18 to 4 against the 36 degrees 30 minutes provision. Some southerners who endorsed Thomas's constraint apparently did so to get a slave state (Missouri) west of the Mississippi River at a time when only Florida remained for slavery's expansion in the East, and because of a belief that much of the remaining land in the West was desert.

The compromise's 36 degrees 30 minutes line helped to preserve sectional peace for more than thirty years, and might have done so longer had not Texan annexation and the Mexican War greatly enlarged the national domain and caused new sectional divisions over slavery's expansion. Without Congress's repeal of Thomas's provision in the Kansas-Nebraska Act of 1854, it is conceivable that the Civil War would have been considerably delayed, or even prevented. In a postmortem commentary on the Missouri Compromise, U.S. Supreme Court Chief Justice Roger B. Taney's opinion in the Dred Scott case (1857) contended that the already repealed 36 degrees 30 minutes line had been unconstitutional because it violated the property rights of southerners guaranteed by the Fifth Amendment of the U.S. Constitution. Taney's ruling outraged many northerners, contributing to pre–Civil War sectional tensions.


Cooper, William J. Liberty and Slavery: Southern Politics to 1860. New York: Knopf, 1983.

Dangerfield, George. The Era of Good Feelings. New York: Harcourt, Brace and World, 1952.

Freehling, William W. The Road to Disunion. Vol. 1, Secessionists at Bay, 1776–1854. New York: Oxford University Press, 1990.

Moore, Glover. The Missouri Controversy, 1819–1821. Lexington: University of Kentucky Press, 1953.

Morrison, Michael A. Slavery and the American West: The Eclipse of Manifest Destiny and the Coming of the Civil War. Chapel Hill: University of North Carolina Press, 1997.

Remini, Robert V. Henry Clay: Statesman for the Union. New York: Norton, 1991.

Zeitz, Joshua Michael. "The Missouri Compromise Reconsidered: Rhetoric and the Emergence of the Free Labor Synthesis." Journal of the Early Republic 20, no. 3 (Fall 2000): 447–485.

Robert E.May

See alsoCivil War ; Dred Scott Case ; Kansas-Nebraska Act ; Mason-Dixon Line ; Sectionalism ; Slavery ; Tallmadge Amendment .

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Missouri Compromise

Missouri Compromise, 1820–21, measures passed by the U.S. Congress to end the first of a series of crises concerning the extension of slavery.

By 1818, Missouri Territory had gained sufficient population to warrant its admission into the Union as a state. Its settlers came largely from the South, and it was expected that Missouri would be a slave state. To a statehood bill brought before the House of Representatives, James Tallmadge of New York proposed an amendment that would forbid importation of slaves and would bring about the ultimate emancipation of all slaves born in Missouri. This amendment passed the House (Feb., 1819), but not the Senate. The bitterness of the debates sharply emphasized the sectional division of the United States.

In Jan., 1820, a bill to admit Maine as a state passed the House. The admission of Alabama as a slave state in 1819 had brought the slave states and free states to equal representation in the Senate, and it was seen that by pairing Maine (certain to be a free state) and Missouri, this equality would be maintained. The two bills were joined as one in the Senate, with the clause forbidding slavery in Missouri replaced by a measure prohibiting slavery in the remainder of the Louisiana Purchase north of 36°30′N lat. (the southern boundary of Missouri). The House rejected this compromise bill, but after a conference committee of members of both houses was appointed, the bills were treated separately, and in Mar., 1820, Maine was made a state and Missouri was authorized to adopt a constitution having no restrictions on slavery.

A provision in the Missouri constitution barring the immigration of free blacks to the state was objectionable to many Northern Congressmen, and necessitated another congressional compromise. Not until the Missouri legislature pledged that nothing in its constitution would be interpreted to abridge the rights of citizens of the United States was the charter approved and Missouri admitted to the Union (Aug., 1821). Henry Clay, as speaker of the House, did much to secure passage of the compromise—so much, in fact, that he is generally regarded as its author, even though Senator Jesse B. Thomas of Illinois was far more responsible for the first bill. The 36°30′ proviso held until 1854, when the Kansas-Nebraska Act repealed the Missouri Compromise.

See studies by G. Moore (1953, repr. 1967) and R. H. Brown (1964).

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Missouri Compromise


Between 1815 and 1850, the politics of the United States became increasingly sectional. The question of slavery dominated the issues dividing the new republic. An increasing number of northerners viewed slavery as morally wrong and insisted that government abolish the system, while most southerners viewed slave labor as essential to their economic prosperity and to that of the nation.

Both the North and the South looked to the newly settled western territories to expand their interests. In 1818 when the Territory of Missouri (part of the Louisiana Purchase of 1803) applied for statehood, there were 11 free states and 11 slave states, giving both sides equal representation in the U.S. Senate. (Because of their populations, the free states dominated the U.S. House of Representatives.) Congress began debating the question of whether to admit new states as free or as slave states. In an effort to preserve the delicate North-South political balance, Congress agreed to the Missouri Compromise in 1820.

The Missouri Compromise provided for Maine to be admitted to the Union as a free state, Missouri as a slave state, and designated as free territories north of the Louisiana Purchase (the present-day southern border of Missouri), with the exception of the state of Missouri.

By the 1850s the issue of the extension of slavery had become very controversial. In 1854 the federal legislature again considered the problems of organizing and admitting new states to the Union. This time the Kansas Territory was under consideration. In another compromise, the territory was carved up to form two states, Kansas and Nebraska, and the slavery status of each would be decided by popular sovereignty (the voters in each state). The Kansas-Nebraska Compromise also repealed the anti-slavery clause of the Missouri Compromise, which had pronounced the northern territories free. Violence ensued, especially in Kansas where anti-slavery and pro-slavery adherents squared off in a series of deadly skirmishes, deepening the North-South schism. In 1857 the U.S. Supreme Court's decision in the case of Dred Scott (17951858), a slave who had sued for his freedom on the basis of having traveled with his owner in the free territory north of the 36th parallel, declared the Missouri Compromise unconstitutional.

See also: Abolition, Louisiana Purchase, Dred Scott Case, Slavery, Tallmadge Amendment

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"Missouri Compromise." Gale Encyclopedia of U.S. Economic History. . 13 Dec. 2017 <>.

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Missouri Compromise

Missouri Compromise (1820–21) Effort to end the dispute between slave and free states in the USA. Largely the work of Henry Clay, it permitted Missouri to join the union as a slave state at the same time as Maine joined as a free state, preserving an equal balance between slave and free.

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Missouri Compromise

Missouri Compromise an arrangement made in 1820 which provided that Missouri should be admitted to the Union as a slave state, but that slavery should not be allowed in any new state lying north of 36° 30′.

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