Zoe Palaiologina (), whose name was later changed to Sophia Palaiologina (; ca. 1449 – 7 April 1503), was a Byzantine princess, member of the Imperial Palaiologos family, and Grand Princess of Moscow as the second wife of Grand Prince Ivan III. Through her eldest son, Vasili III, she was the grandmother of Ivan the Terrible, the first Tsar of All Russia. Family Zoe was born in the Morea in 1449. Her father was Thomas Palaiologos, Despot of the Morea and younger brother of the last Byzantine Emperor, Constantine XI Palaiologos (). Her mother was Catherine, the only legitimate daughter and heiress of Centurione II Zaccaria, the last independent Prince of Achaea and Baron of Arcadia. The marriage between Thomas Palaiologos and Catherine Zaccaria produced four children: Helena (later wife of Lazar Branković, Despot of Serbia), Zoe, Andreas, and Manuel. In Italy The fall of the Byzantine Empire in 1453 was a turning point in Zoe's life. Seven years later, in 1460, the Ottoman army attacked Morea and quickly breached the Hexamilion wall across the Isthmus of Corinth, which was too long to be effectively manned and defended by Thomas' forces. Thomas and his family escaped to Corfu and then to Rome, where (already recognized as the legitimate heir to the Byzantine Empire by the Pope) he made a ceremonial entrance as Byzantine Emperor on 7 March 1461. Catherine remained in Corfu with her children and died there on 16 August 1462. Zoe and her brothers remained in Petriti, a fishing port on the southeast coast of Corfu, until 1465, when their dying father recalled them to Rome. Thomas Palaiologos died on 12 May 1465. Zoe and her brothers were adopted by the Papacy after her father's death. Her name, Zoe, was changed to Sophia. Born and raised in the Orthodox religion, it is possible that she was educated as a Catholic in Rome. She spent the next years in the court of Pope Sixtus IV. The care of the Imperial children was assigned to a famous Greek humanist, theologian and scholar, Cardinal Basilios Bessarion. The Cardinal's surviving correspondence shows that the Pope took an interest in the welfare and development of Sophia and her brothers. They received 3,600 crowns (in payments of 200 crowns per month) for their clothes, horses and servants, and an additional 100 crowns for the maintenance of a modest household that included a doctor, a