Fall of Constantinople

In 1453, the Ottoman sultan Mehmed II captured Constantinople, the last stronghold of the Byzantine Empire, ending the eastern continuation of the Roman state after roughly a thousand years. The city had been the capital of Christian Orthodox civilization since Constantine the Great refounded it in the fourth century, and its fall is often used to mark the close of the Middle Ages, though historians treat such dividing lines as convenient rather than exact.

By the fifteenth century, the Byzantine Empire was a shadow of its former self. The Fourth Crusade had sacked the city in 1204, and although Byzantine rulers recovered it in 1261, the empire never regained its earlier strength. Ottoman expansion had meanwhile swallowed Anatolia and much of the Balkans, leaving Constantinople an isolated enclave surrounded by Ottoman territory. Emperor Constantine XI sought help from the West, and the Church's brief agreement on union with Rome was deeply unpopular among many Orthodox Greeks. Little substantial aid arrived, apart from some Genoese and Venetian volunteers.

Mehmed II, a young and ambitious ruler who came to the throne for the second time in 1451, made the conquest of the city a central goal. His forces besieged Constantinople beginning in the spring of 1453. The city's great Theodosian land walls had withstood attackers for centuries, but the Ottomans brought up large siege cannon, which pounded the fortifications. The Byzantines had stretched a chain across the Golden Horn to protect the harbor, and the Ottomans reportedly moved ships overland to bypass it, forcing the defenders to spread their limited numbers even thinner. Estimates of the defenders vary, but most agree they were outnumbered many times over, with only a few thousand fighting men.

The final assault came at the end of May, and the walls were breached. Constantine XI is believed to have died fighting, though the details of his death are uncertain. Ottoman troops then plundered the city, and many residents were killed or enslaved. Mehmed soon entered the city and converted the Hagia Sophia into a mosque.

Constantinople, later widely called Istanbul, became the Ottoman capital and remained the center of a vast empire for nearly five hundred years. Mehmed took the title of Roman Caesar alongside his Islamic titles, presenting himself as heir to the city's imperial tradition. The conquest gave the Ottomans control over key trade routes between Europe and Asia. Some older accounts claim it directly inspired European voyages of exploration, but historians now see that link as overstated, since Portuguese expeditions were already under way. Greek scholars who fled westward did contribute to the Renaissance, though they were part of a movement that had already begun.