He was born at Trebizond, an Anatolian Black Sea port. The year of his birth has been given as 1389, 1395 or 1403. He was educated at Constantinople, and went in 1423 to the Peloponnese to hear Gemistus Pletho expound the philosophy of Plato. On being tonsured monk, he adopted the name of an old Egyptian anchorite Bessarion, whose story he has related. In 1437, he was made metropolitan of Nicaea by the Byzantine Emperor John VIII Palaeologus, whom he accompanied to Italy in order to bring about a reunion between the Orthodox and Catholic churches. They had been separated since the Schism of 1054, but the emperor hoped to use the possibility of re-uniting the churches to obtain help from Western Europe against the Turks.