Constantine XI Palaiologos
In 1448, John VIII died without children, and as his favored successor, Constantine was proclaimed emperor on 6 January 1449. Constantine's brief reign would see the emperor grapple with three primary concerns. First, there was the issue of an heir, as Constantine was also childless. Despite attempts by Constantine's friend and confidant George Sphrantzes to find him a wife, Constantine ultimately died unmarried. The second concern was the religious disunity within what little remained of his empire. Constantine and his predecessor John VIII both believed a union between the Orthodox and Catholic Churches was needed to secure military aid from Catholic Europe, but much of the Byzantine populace opposed the idea. Finally, the most important concern was the growing Ottoman Empire, which by 1449 completely surrounded Constantinople. In April 1453, the Ottoman Sultan Mehmed II laid siege to Constantinople with an army perhaps numbering as many as 80,000 men. Even though the city's defenders may have numbered less than a tenth of the sultan's army, Constantine considered the idea of abandoning Constantinople unthinkable. The emperor stayed to defend the city and on 29 May, Constantinople fell. Constantine died the same day. Although no reliable eyewitness accounts of his death survived, most historical accounts agree that the emperor led a last charge against the Ottomans and died fighting.