Imperial Ottoman

History · Article

The Fall of Constantinople (1453)

The 1453 siege and conquest of Constantinople by the Ottoman sultan Mehmed II, ending the Byzantine Empire and establishing the Ottomans as a world power.

The fall of Constantinople on 29 May 1453 was one of the decisive events of the late Middle Ages. The conquest by the Ottoman sultan Mehmed II ended the Byzantine Empire, which had endured in various forms for more than a thousand years, and it transformed the city of Constantinople into the capital of the Ottoman state. The event sent shockwaves through the Christian world, changed the patterns of Mediterranean trade, and established the Ottomans as a world power. The events of 1453 are central to the Ottoman golden age that followed, and the dynasty that conquered the city is traced in the history of the Ottoman Empire.

The state of the Byzantine Empire in 1453

By the mid-fifteenth century, the Byzantine Empire was a small and impoverished state, reduced to a few square miles around Constantinople, a handful of islands in the Aegean, and the Peloponnese. The last emperor, Constantine XI Palaiologos, had come to the throne in 1449 with the explicit aim of preserving what remained. The empire depended on subsidies from the pope and the Italian maritime republics, on the goodwill of the Ottoman sultan, and on the legendary strength of the Theodosian walls. The dynasty that the defenders faced had been building toward this moment for more than a century, as described in the rise of the Ottoman Empire.

The walls of Constantinople, built in the early fifth century by the emperor Theodosius II, had held the city against every assault for nearly a thousand years. They were a triple system: an outer wall, an inner wall, and a moat, defended by 192 towers. The city was also defended by the famous Greek fire, an incendiary weapon whose composition had been a closely guarded state secret for centuries.

The Ottoman preparation

Mehmed II, who came to the throne in 1451 at the age of nineteen, was determined to take the city. He spent the first two years of his reign preparing an enormous army, a large fleet, and a massive siege train. The famous bombard cast by the Hungarian engineer Orban, a gun of unprecedented size, required sixty oxen to move and could hurl a stone ball of several hundredweight.

The Ottomans also secured the cooperation of the Greek Orthodox patriarch and the Genoese colony of Pera (Galata) across the Golden Horn. The Genoese agreed to remain neutral, in return for the protection of their commercial interests. The Orthodox population of the city was a major source of information, and many of its members welcomed the prospect of Ottoman rule as a relief from the Latin policies of the dynasty.

The siege

The siege began in early April 1453. The Ottoman army has been estimated at between 80,000 and 200,000 men, and the defending force at perhaps 7,000. The disproportion was overwhelming, but the walls had held off many larger armies, and the defenders were determined.

The siege made use of the new gunpowder artillery in ways that had not previously been seen. The bombard cast by Orban fired on the walls from 12 April, but the wall was thick and the gunpowder expensive. The Ottomans also built a pontoon bridge across the Golden Horn to bypass the chain that closed it, an engineering achievement that allowed the army to be resupplied from the north.

The defense was led by the Genoese condottiere Giovanni Giustiniani, who arrived with a small force and took command of the land defenses. The emperor Constantine XI took personal command of the defense of the Mesoteichion, the central section of the wall. The garrison included Catalans, Genoese, Venetians, and the small remnant of the Byzantine army. The Ottoman army that faced them had been built up over more than a century, beginning with the modest forces of Osman I and developing into the most powerful army in the Mediterranean by the time of Mehmed II.

The final assault

In the early hours of 29 May, the Ottomans launched their final assault. The attack was made in three waves, and after the first two were repulsed, a third wave, made up of bashi-bazouks, irregulars, found an unguarded entrance through the Kerkoporta, a small postern in the wall. The defense collapsed, and the city was overrun.

Constantine XI died in the fighting, according to tradition, fighting at the gate of St. Romanus. The patriarch and many of the notables were taken prisoner. The city was given over to pillage for three days, in accordance with the customary rules of Ottoman siege warfare, and then the sultan entered the city and announced the restoration of order.

The aftermath

The fall of Constantinople had consequences that radiated through the next centuries. The Byzantine Empire was finally extinguished, and the long succession of Greek-speaking states that traced their origin to the Roman Empire of Constantine was at an end. The patriarch was reinstated, and the Orthodox church entered a new phase in which it was led from Istanbul and was the head of the Orthodox world in the Ottoman lands.

The event sent a shock through the Christian world. The pope proclaimed a crusade, and the Portuguese pushed around Africa in search of an alternative route to Asia. The Hagia Sophia, the great church of Byzantine Christianity, was converted into a mosque. The Greek scholars who fled the city in the following decades, taking manuscripts with them, contributed to the Italian Renaissance. The dynasty that had brought the city to the point of conquest is traced in the rise of the Ottoman Empire, and the political consequences of the conquest would play out for centuries, culminating in the Battle of Mohács and eventually in the territorial losses recorded in the Treaty of Karlowitz.

For the Ottomans, the conquest was the foundation of their imperial identity. Mehmed II took the title of Caesar and Sultan of the Two Continents. The city, which he renamed Istanbul, was rebuilt as a Muslim capital, with new mosques, palaces, and a population drawn from across the empire. The fall of Constantinople was both an end and a beginning, and the moment is central to the longer history of the Ottoman Empire that followed. The conquest also reshaped the politics of central Europe, setting up the campaigns that would culminate in the Battle of Mohács and the long struggle for Hungary that ended only with the Treaty of Karlowitz of 1699.