1453: the Fall of Constantinople

AS EARLY AS 1354 THE OTTOMANS HAD SETTLED AT GALLIPOLI, on the eastern side of the Bosporus, directly across the strait from Constantinople, and in time they surrounded Byzantine territory. Ensnared in a noose, the panicked Byzantine emperors sought military help from the west. Byzantine Emperor John VII, sensing the direness of the situation, was even willing to give up autonomy and embrace reunification with Rome in order to receive aid, but such a move was unpopular with the Byzantines. The Catholic Church had split into Roman and Eastern factions in 1054, and the hostility between the two was so great that even the most devoted Eastern Orthodox Christians favored Muslim rule over being under the heel of the Roman Church. By 1450 the Byzantine Empire had shrunk to the city of Constantinople and a few miles outside the city walls, and in 1452 Mehmed II began building a fortress on the European side of the Bosporus, just a few miles north of Constantinople and directly across the straits from the Gallipoli fortress that had been built by his great-grandfather. Coupled together, these two fortresses ensured control of the traffic in the Bosporus and defended against European attacks from the Genoese colonies on the Black Sea coast to the north. Mehmed named his new fortress ‘throat-cutter,’ and in October he ordered a garrison of soldiers to be established in the Peloponnese to block Byzantine’s allies from helping him in the coming siege.

Constantine XI, who could trace his lineage all the way back to Constantine the Great from the 4th century A.D., knew what was coming. Like John VII he was willing to acquiesce to the demands of Rome in order to receive assistance, but Rome couldn’t help: she lacked the power to pull the strings (and purses) of western rulers, and even if she did have that power, France and England were exhausted after the Hundred Years War, a recently reunified Spain was in the throes of the Reconquista, and the German Principalities were squabbling as was their time-honored custom. Constantine received meager help from the Italian states, but nowhere near enough to stem the tide of the coming Ottoman onslaught. Though a European fleet departed Rome in February 1453, it was too late. A number of Byzantine soldiers could read the writing on the wall and fled the city, and Constantine’s attempts to placate Mehmed with gifts ended with his ambassadors being executed. 

Constantine wagered that Mehmed’s attack on Constantinople would come from the sea; after all, the city’s landward fortifications, known as the Theodosian Walls, stretched twenty kilometers and were the strongest fortifications in existence. They’d proved their worth time again, preventing numerous besiegers from cracking their way into the city. In addition to the walls, there was a sixty-foot-wide moat that fronted inner and outer crenellated walls laced with towers every one hundred fifty feet. Feeling somewhat secure from a landward attack, Constantine ordered a chain of obstacles to be constructed along the Golden Horn (the primary inlet of the Bosporus) to prevent Ottoman ships from closing in on Constantinople’s seaward side. Constantine, lacking significant defenders, had to put his hope in the city’s fortifications. Modern estimates give him seven thousand fighting men, two thousand of which were foreigners. While some were well-trained and well-armed, most were nothing more than armed civilians and sailors, volunteer forces, and even a spattering of monks. These men, and a fleet of twenty-six ships, were tasked with protecting the fifty thousand civilians behind the city walls, a number that included numerous refugees who had fled to the city as the Ottoman forces marched ever-nearer the capital. 

The twenty-one-year-old Mehmed II began his siege on 6 April 1453, and his forces made Constantine’s look like a paltry handful. Modern estimates put his numbers at around fifty to eighty thousand soldiers, including up to ten thousand Janissaries (elite Ottoman infantry, and the first modern standing army in Europe), seventy cannons, and thousands of Christian troops, including fifteen hundred Serbian cavalry supplied by a Serbian lord who’d been forced to kneel before Mehmed (and who had, ironically, paid for the upkeep and repairs of some of Constantinople’s walls just months before). While besieging the city, Mehmed ordered his soldiers to wipe out Byzantine bastions and castles outside the walls, and he turned his attention to the Golden Horn. Mehmed brought his cannon to bear on the walls, pounding them day after day, and he ordered his fleet to try and penetrate the Golden Horn.  The chained obstacles prevented their ships from closing in on the city, and on 20 April a fleet of Christian ships battled with the Ottomans and managed to slip into the harbor. Their reinforcement of the city’s garrison humiliated Mehmed, and the naval commander responsible for their slippage through the Ottoman cordon was brought before the sultan to answer charges. The commander’s companions testified to his bravery during their tangle with the Christian ships, and Mehmed chose to spare his life. 

Since the Golden Horn couldn’t be penetrated, Mehmed played with the idea of bringing his ships into the harbor by crossing a stretch of undefended land. He ordered a road of greased logs built across the finger of land, and Ottoman ships were ferried across and guided into the Horn behind the obstacles. A week later, on 28 April, the Byzantines tried to destroy the enemy vessels using fire ships, but the Ottomans had been warned of their plans and repulsed their attackers. Forty Italians escaped sinking ships and managed to swim to the northern shore where they were apprehended by the Ottomans; Mehmed ordered them impaled on stakes in sight of the city’s defenders. The Byzantines responded by bringing their Ottoman prisoners, numbering around two hundred sixty, up onto the walls. There they executed them before the eyes of the besieging army. 

the Basilica

Mehmed couldn’t assault Constantinople from the seaward side, so he was forced to try and overcome the city’s legendary walls. To this end he launched waves of vicious attacks against the walls, and he coupled this with overwhelming firepower. Legend has it that his siege of Constantinople is the first time gunpowder cannons were brought to bear on city walls, but this is inaccurate; at the same time, however, it was his overwhelming use of cannon that serves as a prelude to the type of siege warfare that would become endemic throughout the early modern era. Mehmed’s artillery train consisted of seventy medium-sized cannons, and he even casted bombards outside the walls. His most famous cannon was the ‘Basilica,’ which was twenty-seven feet long and capable of firing a six-hundred-pound stone ball over a mile. The Basilica was the work of a man by the name of Urban; he was either Hungarian or German, and he brought cannon foundry to the next level. He’d tried to sell his skills to the Byzantines, but as they were unable to afford him, he approached Mehmed with the claim that his Basilica design could blast ‘the walls of Babylon itself.’ Mehmed had money whereas the Byzantines did not, and he hired his services. In three months Urban constructed the gun at Edirne, the Ottoman capital, and from there it was dragged by sixty oxen and four hundred men to throw its weight against Constantinople. The Basilica, however, wasn’t without its drawbacks: six-hundred-pound cannonballs weren’t easy to find, it took three hours to reload, and it likely collapsed under its own recoil after six weeks. 

Mehmed’s cannons fired on the city’s walls for weeks, but the Byzantines were able to repair most of the damage. The city would have to be taken by force, and to this end Mehmed ordered assault after assault upon the walls. A Venetian surgeon Niccolo Barbaro gives us a glimpse of what these assaults looked like, writing, ‘[The defenders] found the Turks coming right up under the walls and seeking battle, particularly the Janissaries… and when one or two of them were killed, at once more Turks came and took away the dead ones… without caring how near they came to the city walls. Our men shot at them with guns and crossbows, aiming at the Turk who was carrying away his dead countryman, and both of them would fall to the ground dead, and then there came other Turks and took them away, none fearing death, but being willing to let ten of themselves be killed rather than suffer the shame of leaving a single Turkish corpse by the walls.” When the assaults failed, Mehmed ordered sappers to dig beneath the walls and place explosives to bring them down. The defenders counter-mined, breaching the Ottoman tunnels with their own and pushing the miners back in hot-and-heavy hand-to-hand combat in the dimly lit tunnels, often using ‘Byzantine fire’—an incendiary weapon developed sometime in the mid-600s—to push them back out the way they came. When the Byzantines captured two Turkish officers, they tortured them until they gave up the locations of all the sapping tunnels, enabling the defenders to countermine and destroy each one. Below are some artistic representations of the siege of Constantinople:

Mehmed, frustrated that his cannons, assaults on the walls, and sapping tunnels were getting him nowhere, sent an ambassador to the city on 21 May and offered to lift the siege if the Byzantines surrendered. He promised to allow Constantine and the civilians to leave the city with their possessions, and he’d recognize the emperor as the governor of the Peloponnese. He also guaranteed the safety of anyone who decided to remain in the city after it changed hands. The emperor countered by offering to pay higher tributes to Mehmed and to recognize the status of all conquered castles and lands in the hands of the Turks as Ottoman possessions. He would absolutely not, however, relinquish the city. The negotiations came to nothing, and an irritated—and desperate—Mehmed decided to throw at the walls everything he had in one last gambit to bring Constantinople to its knees. 

On 28 May, as the Ottomans prepared for their final assault, Christian religious processions were held in the city. Come evening a last ceremony was held in the Hagia Sophia, in which the emperor and representatives of both the Latin and Greek churches partook. Mehmed’s assault began shortly after midnight on the 29th: his Christian troops attacked first, followed by waves of the irregular azaps (ill-equipped and ill-trained peasant militias). Cannon fire had weakened the walls in the city’s northwest quadrant, and Anatolian soldiers managed to breach their way through, though the Byzantine defenders expelled them. Mehmed then launched his elite Janissaries into the fray. When the Genoese general in charge of the Byzantine troops was gravely wounded, he was evacuated from the melee, much to the consternation of the defenders. Panic infected their ranks, and the Genoese soldiers began to break from the fight and flee for the harbor. The emperor and his troops were left to defend against the Ottomans alone, and when Ottoman flags were seen flying above a small city gate, the panic became infection and resistance crumbled. The Janissaries took advantage of the break in morale; Greek soldiers ran home to protect their families; the Venetians ran to their ships; and several Genoese ships put out from the Horn and managed to escape through the Ottoman blockade. Many soldiers committed suicide by jumping off the city walls, or surrendered to the Ottomans in hope of mercy. Barbaro describes blood flowing in the city ‘like rainwater in the gutters after a sudden storm,’ and the bodies of Turks and Christians floating in the sea ‘like melons along a canal.’ Legend tells us that Constantine, throwing aside his purple royal regalia, led the final charge against the Janissaries, and perished in the battle in the streets; however, the Venetian surgeon quoted earlier reports in his diary that the emperor hanged himself the moment the Turks broke through the city. In whatever way death came, the demise of Emperor Constantine XI Palaeologus, whose imperial lineage stretched back more than 1400 years to Augustus Caesar, marked the end of the Empire that Augustus had inaugurated. 

Mehmed II enters Constantinople

Once the Ottomans were firmly inside the city, they fanned out along the city’s main thoroughfare and marched past the great forums and the Church of the Holy Apostles. Mehmed had sent an advance guard to protect these buildings so as not to arouse the anger of the Christian citizens. The Ottomans converged upon the Augusteum, the vast square that fronted the Hagia Sophia. The church’s bronze gates were barred by a throng of civilians bunkering down in the sanctuary in hope of divine protection. Once the doors were breached, the troops separated the congregants according to what price they might bring in the eastern slave markets. By the end of the battle, four thousand Byzantines, both soldiers and civilians, had died, and thirty thousand inhabitants were enslaved. 

In political terms, the fall of Constantinople to the Ottomans didn’t amount to much. The skeletal remnants of the Byzantine Empire had been an ineffective barrier to Ottoman expansion, and over time the city had declined to the point that it was commercially and politically unimportant. Ottoman dominion didn’t affect east-west trade to any great degree, and it didn’t result in an exodus of Byzantine scholars and manuscripts to Italy. The impact was largely psychological: it shocked the Christian world. As historian Kevin Kiley writes, ‘For more than one thousand years, this Christian Roman Empire played a huge political and cultural role in the histories of both the East and West; in some ways, the years of its existence mark the span of the Middle Ages, and its passing symbolizes the End of an Era.’ He continues, ‘It can be argued that perhaps the most enduring legacy of the eastern Roman Empire was that, not by design or long term strategy, they succeeded in keeping the Muslim or Turkish enemies in the east out of central and western Europe until those regions could properly defend themselves. Ultimately the Byzantine emperors acted as the bulwark against an aggressive Islam that was bent on ever-expanding western conquest. By the time the Ottomans finally took Constantinople, however, and ended the eastern Roman Empire in fire and rubble, the nations of the west were ready to take on the Muslim onslaught.’

Mehmed II changed the name of Constantinople to Istanbul (though the name change didn’t become official until as recently as 1930) and made it, rather than Edirne, his Ottoman capital. Through the latter days of his reign he subjugated Morea, Serbia, Bosnia, and parts of Herzegovina. He drove the Genoese from their Black Sea colonies, forced the Khan of Crimea to become his vassal, and engaged in a naval war with the Venetians. By his death in 1481, the Ottomans had acquired massive power on land and sea, and the Black Sea had become a ‘Turkish Lake.’ The Ottomans, however, weren’t finished: in the 1500s, Mehmed’s successor Suleiman II ‘The Magnificent’ would carry the Ottoman Empire to the height of its power.