Who took Constantinople, and how?
The Ottoman Sultan Mehmed II took Constantinople, the Byzantine capital, on 29 May 1453, after a siege that began on 6 April and lasted about eight weeks. He won with giant cannon cast by the Hungarian engineer Urban (Orban), by hauling his ships overland into the Golden Horn around its harbor chain, and with a dawn assault that broke through the land walls. The last emperor, Constantine XI, died in the fighting, and the Byzantine Empire ended with the city.4
For a thousand years the great land walls of Constantinople had withstood every siege. The crusaders who sacked the city in 1204 broke in mainly from the harbor side. In the spring of 1453 a 21-year-old sultan arrived with some of the largest cannon of the age, determined to take the city that had defied his ancestors and to end the Roman Empire once and for all.5
The last Roman city
By 1453 the Byzantine Empire, the Greek-speaking heir of the Roman Empire, had shrunk to Constantinople and the land just west of it, together with the Despotate of the Morea in the Peloponnese, ruled by the emperor's brothers. Its population, which had run to hundreds of thousands in the 12th century, had fallen to perhaps 40,000 to 50,000, and fields and orchards filled much of the space within the walls. Around it the Ottoman Empire had spread across nearly all of the Balkans and most of Anatolia, and the city had become an Ottoman vassal.6
Mehmed's father, Murad II, had besieged Constantinople in 1422 and had to give up to put down a rebellion. Mehmed, who came to the throne for the second time in 1451, meant to finish the work. In 1451 he renewed his father's peace with Venice and agreed a three-year truce with Hungary, to keep them out of the coming war.7
A fortress on the Bosporus
The first blow fell in 1452, before a single shot was fired at the city. At the narrowest point of the Bosporus, on the European shore, Mehmed built a fortress the Turks called Boğazkesen, later Rumeli Hisarı, to control the passage between the Black Sea and the Mediterranean. Its guns made the point at once. When a Venetian ship refused to stop for inspection in November 1452, it was sunk, and its captain was captured and impaled.8
Mehmed's great guns
Mehmed's real answer to the walls was artillery on a scale never seen before. A Hungarian gun founder named Urban, or Orban, had first offered his services to Constantine XI, who could not pay his price. Mehmed paid far more. Gibbon, following the chroniclers, says the stone ball of the largest of Urban's guns weighed over 600 pounds, and that sixty oxen and hundreds of men took nearly two months to drag the monster the 150 miles from Adrianople.9
By March 1453 Urban's cannon had arrived outside the city. Britannica counts 69 guns in the Ottoman siege lines and an army of 60,000 to 80,000 soldiers, the range most modern historians accept. Sphrantzes, the emperor's secretary and an eyewitness, wrote of 200,000 men on the land side; Gibbon, following a later, expanded version of his chronicle, gives 258,000. A fleet under Baltaoğlu Süleyman Bey, with some 31 large and medium warships and nearly 100 smaller craft, closed the sea approaches.10
Defenders and walls
Constantine XI begged the Christian powers for help and got little. Pope Nicholas V pressed instead for the union of the Orthodox and Catholic churches, and when union was proclaimed the people of the city rioted. Venice sent ships and men late. The help that mattered most came from a Genoese captain, Giovanni Giustiniani Longo, a famous expert in siege warfare, who arrived in January 1453 with 700 soldiers he had raised himself in Genoa, Chios and Rhodes; the emperor made him commander of the land walls.12
When the emperor's secretary George Sphrantzes counted the men able to bear arms, he found fewer than 5,000 Greeks. With the foreigners, the defense came to about 7,000 fighting men, to hold walls that ran for miles. The land walls, the Theodosian Walls, stretched about 4 miles (6.5 km) from the Sea of Marmara to the Golden Horn, a double line of ramparts behind a moat, the inner wall up to 40 feet high. A great chain closed the mouth of the Golden Horn, guarded by a small fleet of Greek and Italian ships.13
The numbers depend on whom one asks. The eyewitness Jacopo Tedaldi, as Britannica reports him, counted 30,000 to 35,000 armed townsmen but only 6,000 to 7,000 trained soldiers. Gibbon writes of some 2,000 foreigners under Giustiniani besides the Greeks, though the shorter chronicle of Sphrantzes counts only about 200. Either way the land walls, never once breached by an enemy in the thousand years since they were built, would have to be held by a few men to every yard. Giustiniani put most of them on the land walls, where the middle stretch, the Mesoteichon, looked weakest.14
Ships over the hill
The bombardment opened on 6 April. The guns soon brought down sections of the wall, and on 18 April a night assault on the Mesoteichon was beaten off. From then on the cannon fired every day, and every night the defenders filled the breaches with earth, timber and rubble. On 20 April four Christian relief ships fought their way through the Ottoman fleet and past the chain into the harbor, a humiliation that cost Baltaoğlu his command.15
Mehmed's reply became the most famous episode of the siege. Behind the Genoese suburb of Galata he laid a road of greased planks over the hill, and his men dragged some 70 to 80 galleys and smaller ships on rollers and carts from the Bosporus down into the Golden Horn. By 22 April they were afloat inside the harbor, behind the chain. Now the sea walls along the Horn had to be manned too, and the defenders were stretched thinner still. Mehmed then had a floating bridge of casks and timbers laid across the upper Horn and mounted a cannon on it, bringing his guns closer to the harbor walls.16
Through May the pressure never let up. Ottoman sappers dug mines toward the walls and the defenders countermined and destroyed them. A great wooden siege tower was rolled against the wall near St. Romanus and burned by the defenders in the night. The garrison grew hungrier and more exhausted, and no relief fleet appeared.17
The final assault
Mehmed offered terms one last time and Constantine refused. On the night of 28 May Greeks and Latins together held a final service in Hagia Sophia. Before dawn on 29 May, a Tuesday, the Ottoman army attacked from three sides at once, by land and by water, in waves. First came the irregulars, then the better-armed troops of Anatolia, and finally the Janissaries, the sultan's elite infantry.18
For hours the defenders held the breach near the Gate of St. Romanus. Then Giustiniani was badly wounded by a shot and carried from the wall, and his men's resolve broke with him. According to one account, the Janissaries found a small postern, the Kerkoporta, left open and raised the Ottoman flag on the walls. Fresh Janissaries pushed into the gap at St. Romanus and the line gave way.19
What happened to Constantine XI is not certain. Britannica records that he was reported killed either fighting near the breach or trying to reach a boat. The Foundation of the Hellenic World says simply that the last emperor fell fighting on the walls. Gibbon repeats the later story that his body was found under a heap of the slain and known by the golden eagles embroidered on his shoes. No grave has ever been identified.20
The sack and the new capital
The city was given over to plunder. The Foundation of the Hellenic World says the looting lasted three days and three nights. Many Venetians and Genoese escaped to their ships in the Golden Horn.21
Mehmed rode into the city to Hagia Sophia, the greatest church in Christendom, and ordered it turned into a mosque. He then ordered the looting to stop, on that same day according to Britannica, made Constantinople his capital in place of Edirne, and set about repopulating it with people of many faiths. The Greek Orthodox community survived under a new patriarch, Gennadios. Mehmed began to style himself Kayser-i Rûm, Caesar of Rome, heir to the Roman emperors.22
The end of an empire
The fall of Constantinople ended the Byzantine Empire and with it the last continuous thread of the Roman state. For Christian Europe the city that had shielded it from the east for centuries was gone, and the Ottomans held the straits to the Black Sea. Greek scholars had been settling in Italy for more than a generation before 1453, and those who followed after the fall helped carry Greek learning into the Renaissance.23
From its new capital the Ottoman Empire kept expanding for generations, until its defeat at Lepanto in 1571 dented its sea power and its failure at Vienna in 1683 marked the limit of its advance into Europe (see the greatest battles of the Ottoman Empire). The city itself, now Istanbul, remains one of the great cities of the world.24 › Mehmed II the Conqueror
Test yourself on the city's thousand years of wars in the Byzantine battles quiz, or follow the conquerors in the Ottoman battles quiz.
