Maria of Tver (c. 1440–1467)

Grand Princess of Moscow. Born in 1440 or 1442, in Tver, a town northwest of Moscow; died on April 22, 1467; daughter of Prince Boris of Tver and Anastasiaof Mojaisk (d. 1451); betrothed to Ivan III when she was six; married Ivan III (1440–1505), tsar of Russia(r. 1462–1505), on June 2, 1452; children: Ivan the Younger (1456–1490), prince of Moscow (r. 1471–1490, who married Helene of Moldavia ).

The daughter of Prince Boris of Tver and Anastasia of Mojaisk , Maria of Tver was betrothed to Ivan III in 1446, when both were six years old. Ivan's father, Basil II, grand duke of Moscow, was trying to consolidate his position. Little is known of the subsequent years, except that Maria of Tver married Ivan in 1452 and had a son in 1458, and Ivan fought a campaign against the Dnieper Tatars in the same year. He succeeded to the Grand Ducal throne in 1462, aged 22, after his father's death from gangrene. Moscow at that time had not established the principle of primogeniture, by which the oldest son inherited all his father's duchy. Although Ivan received the lion's share, Basil was careful in his will to share almost half of his lands and wealth among his four other sons. Ivan honored the will, but for most of his reign he had to face the anger of his resentful brothers without yielding to them any more than was necessary.

Maria died in 1467. Although she had been forced on Ivan solely for political reasons, her death caused him genuine regret. He was only 27 at the time, and she had borne him only one son. Like all monarchs of the era, he had to think at once of securing the succession by remarrying, lest he outlive this son and expose the state to a fratricidal succession war. Ivan employed a handful of Italian military and architectural advisors and through one of them he learned that the pope, Paul II, was guardian of a princess who might become his new bride. She was Sophia of Byzantium , a huge woman whose uncle had been the last Byzantine emperor, Constantine XI, when that ancient Empire fell to the Turks in 1452.