At dawn on 29 May 1453 the Ottoman army of Sultan Mehmed II made its final assault on Constantinople after a siege of about seven weeks. Janissaries broke into the city, the last Byzantine emperor, Constantine XI Palaiologos, was killed in the fighting, and Mehmed rode in as conqueror. The city became the capital of the Ottoman Empire, and with it ended the last remnant of the Roman Empire. The date is in the Julian calendar then in use; on the Gregorian calendar it would fall on 7 June.
The siege
Mehmed II was only 21 when he set out to take the city. World History Encyclopedia records that his army gathered before the walls on 2 April 1453 and that the bombardment began on 6 April, after his demand for surrender went unanswered; Medievalists.net counts 53 days from the start of the siege to the fall. The Foundation of the Hellenic World speaks of about seven weeks of siege, at the end of which the walls began to show serious cracks.1
The numbers are uncertain. The eyewitness George Sphrantzes gave the Ottomans 200,000 men, a figure modern historians cut to 60,000 to 80,000, according to World History Encyclopedia; the Foundation of the Hellenic World puts the Ottoman army at about 150,000. Sphrantzes counted fewer than 5,000 defenders for some 19 kilometers of walls, while the Foundation gives about 7,000, 5,000 Byzantines and 2,000 foreigners, among them 700 Genoese under Giovanni Giustiniani. World History Encyclopedia adds that the defenders had 26 ships, most of them belonging to Italian colonists.2
Guns and ships
Mehmed's artillery was decisive. A Byzantine quoted by the Foundation of the Hellenic World said that everything was decided by the cannon. World History Encyclopedia describes how the Hungarian founder Urban, unable to get his price from Constantine, cast guns for Mehmed instead, the largest of them able to fire a stone ball of about 500 kilograms but only seven times a day.3
A boom closed the harbor of the Golden Horn to the Ottoman fleet. Mehmed's answer, as World History Encyclopedia tells it, was to have about 70 ships hauled overland on a track behind Galata and launched into the Golden Horn, opening a second front against the sea walls.4
The last assault
On the eve of the attack Greeks and Latins together attended vespers in Hagia Sophia. At dawn on 29 May Mehmed launched the final assault. World History Encyclopedia describes three waves, first irregular troops, then better-armed regulars and finally the Janissaries, and repeats the tradition that the Janissaries got in through a small gate, the Kerkoporta, that had been left open. Constantine XI died fighting on the walls. He had thrown off his imperial insignia, and his body was never certainly identified.5
The sack that followed is described differently. The Foundation of the Hellenic World writes of three days and nights of looting, while World History Encyclopedia says Mehmed entered the city that afternoon and ended the plundering, and estimates that perhaps 4,000 people were killed and more than 50,000 enslaved. Mehmed ordered Hagia Sophia turned into a mosque.6
Istanbul
Constantinople became the capital of the Ottoman Empire. According to World History Encyclopedia, Mehmed let the Orthodox Christian community survive under a new patriarch, Gennadios II, and Byzantine culture lived on, above all in art and architecture. Medievalists.net calls its fall the final end of the Roman Empire, and World History Encyclopedia notes that the last Byzantine outposts, Mistra and Trebizond, fell in 1460 and 1461. The full story of the siege is in our article on the siege of Constantinople, and the conqueror in our biography of Mehmed II.7
