By the middle of the fifteenth century, time had just about ran out for the Byzantine Empire. While the Frankish Crusaders had been driven out of the city of Constantinople, the population of the city was a tenth of the five hundred thousand it had been during its heyday. The Crusaders had killed a large part of the population, but far deadlier had been the constant plagues. Now the city lay half-empty, little more than a collection of populated areas surrounded by the great walls built by Theodosius II a thousand years before. Outside the walls, the Empire had shrunk to little more than a city-state, controlling barely a few miles from the edge of the city. Outside of this, only two parts of the Empire remained – the Prince’s Islands, a series of small islands in the Sea of Marmara, and the Peloponnese, the large island on the southern end of Greece that holds the modern city of Corinth and the ancient city of Sparta. Unfortunately the former was too small and the later too remote to play much role in what was to come.

The Empire was also without allies at this crucial point. The actions of the Crusaders had created an irreparable rift between the Orthodox and Latin churches, and even facing destruction, the people of Constantinople refused to countenance the notion of re-unifying the churches. Even if the Pope had declared a Crusade to defend Constantinople, however, the chances of the Western kingdoms paying it much heed were remote. Gone were the days of absolute papal authority over the kings of Europe – the Reformation was only sixty years away, and the corruption of the church that would lead to it was already eating away at the power of the Pope. Besides, France and England were just concluding the Hundred Years War, the Spanish were completing their Reconquista and the Germans were engaged in civil war. In fact, the two countries closest to the action, the Polish and the Hungarians, had both just been defeated the Ottoman Empire, the same force threatening Constantinople. Only Venice and Genoa stood with Constantinople, and Venice would send its fleet out too late to help, while Genoa would be cut off by the manoeuvrings of the Ottomans. Constantinople stood alone.

The Ottoman Empire, the force threatening the city, literally surrounded it. They had taken advantage of the chaos sown by the Fourth Crusade to snatch up the eastern half of the empire, and then circumvented the city to capture the western half of the empire as well. Now their new Sultan, the 19-year old Mehmed II, was moving to capture the ancient city. His grandfather had built a fort at the mouth of the Bosporus, and Mehmed built another fort across the strait from it. He named it Rumelihisarı, but it also gained a more sinister name – Boğazkesen, which roughly translates as “throat slitter”. While Mehmed spoke of peace with Constantinople, the Emperor, Constantine XI, could see clearly that this was not his true intent. Ironically he owed his throne to Mehmed’s father, Murad, who had acted as a mediator when the Byzantine succession was in question following the death of Constantine’s brother. But Murad had died in 1451, and his son was no friend to the city.

Constantine began organising for the defence of the city, but the dire economic state of the empire left him with little in the way of funds to do so. He was able to stockpile food, and to make some repairs to the Theodosian Walls, but he could not afford to raise a sufficient army to defend the city. The only other Byzantine troops were in the Peloponnese, but Mehmed invaded the area to tie those troops up, and prevent them coming to the capital. Constantine’s poverty even served to strengthen his enemy, when a Hungarian gunsmith named Orban came to the city. Constantine was unable to pay the salary he demanded, so Orban instead offered his services to Mehmed. The Theodosian walls had withstood numerous assaults through the centuries, but now they faced gunpowder and cannon.

The siege began in the winter of 1452. Constantine led an army of 7,000 in the defence of the city, with a tenth of his forces comprising European volunteers (mostly Genoese and Venetian) who had made their way to the city to help defend it. A small number of Venetian ships that were in the area also lent their efforts to defending the city. Against them, however, stood an army of 80,000 soldiers. The elite Janissaries alone may have outnumbered the defenders of the city. Orban created cannons greater than any before seen for the Sultan (his “treachery”, as his countrymen might have seen it, in aiding the infidel was duly rewarded when one of the cannons exploded during the siege, killing him). A fleet of over a hundred ships also bore down on the city from the ocean, against the defender’s 26. The assault was staged from the east of the city, the landward side, while the ships harried them from the east. On the 5^th April 1453, the Sultan arrived and the battle began.

Given his low troop numbers, Constantine elected to man only the outer of the two walls, and even then his men were stretched perilously thin. Constantine and his best troops defended the centre, where a river crossed the walls and they were weakest, while his commanders covered the gates and the sea walls. While he did have some defensive cannons, they were primitive, and the walls were not strong enough to give them the bracing they needed. On the other hand, the cannons of the Ottomans were also primitive, and while they did damage the walls the Byzantines were able to keep up running repairs. The Byzantines knew that they could not repel the assault entirely, but their hope was to hold out long enough for aid to come from Europe.

The Ottomans, meanwhile, did their best to isolate the city. The Prince’s Islands fell to their fleet, as did the few Byzantine fortresses beyond the walls. He was prevented from entering the Golden Horn due to the Great Chain, however. In a brilliant move the previous flaw in the chain (that capturing the far end of it would allow it to be dropped) had been remedied by the simple expedient of placing wooden floats along its length to keep it up. But while they could not breach the chain, they could bypass it. In a mammoth effort, the Sultan had a wooden track laid on the land along the northern end of the strait, and portaged a part of his fleet across. Once the ships were in the bay, they were able to lay siege to the sea walls on that side, drawing defenders away from the main wall. In addition, the supplies the city had been receiving from Genoese colonies on the far side of the bay was cut off – the nominally neutral Genoese had been willing to smuggle supplies, but were not prepared for open conflict to transport them. The Byzantines attempted to use fire ships (a favoured tactic of theirs) to destroy the Ottoman ships, but this failed.

During this time, the Ottomans had attempted to undermine the walls with siege tunnels, but the Byzantines (guided by a siege engineer who is now believed to be a far-afield Scot named John Grant) had managed to penetrate their tunnels and kill the diggers. Despite this, Mehmed determined that the walls in the north west of the city were weakening, and he prepared for a final assault. Prior to this, Mehmed offered Constantine free passage to the Peloponnese in exchange for his surrender of the city, but Constantine refused. This, combined with the lull in attacks cause by the preparations, alerted the Byzantine Emperor that the major attack was imminent. The timing could not have been worse – Venetian blockade-runners had just brought word that the hoped-for Venetian fleet was not coming to save the city. He had large-scale religious processions ordered throughout the city, and prepared his people for the end.

The final assault began with a night attack in the early hours of the 29^th May; fifty-seven days after the siege began. The initial attack consisted of conscripts and irregulars, simply to soften up the defenders, followed by his regular soldiers, with the elite Janissaries making up the final wave. The casualties were high, but the Ottoman soldiers forced their way into the city. The Genoese general was mortally wounded in the fighting and his troops panicked, allowing the Turks to gain a solid foothold within the walls, capturing one of the gates. Constantine, knowing that his city was doomed, tore the imperial insignia from his uniform and led his men in one last futile charge, dying in the streets of the city with his soldiers. The civilians barricaded themselves into the Hagia Sophia, the greatest church in the city, hoping for divine protection. The Ottomans broke the doors in easily, however, and reportedly began immediately separating the congregation out based on how much they would sell for as slaves. Mehmed had the building immediately converted into a mosque – a symbolic gesture that drew a line under the defence of the city. The battle was over.

Mehmed’s men plundered the city for three days. They were more discriminate in their plundering than the crusaders had been, due to their Sultan’s orders. He planned to make Constantinople his capital, and had no wish to rule from the ruins. The number of civilians killed, while still in the thousands, was less than the number killed the last time the city had been conquered. A more sinister concern than simple humanitarianism underlay this however, for to the Ottomans the civilian population were part of the plunder – thirty thousand people, fully half the population of the city, were sold into slavery. The depopulation of the city was almost complete, and like Constantine the Great, Mehmed was forced to order people from all over his empire to move to the city to re-populate it. Twenty-five years later, he had grown the population to eighty thousand – more than it had been before his conquest. By the middle of the 16^th century it was the largest city in Europe, but so complete was the substitution of its inhabitants that even the Christian Greeks who lived there could not name the Byzantine churches that had been closed or co-opted as mosques.

The fall of Constantinople changed the world irrevocably. The trade link between Europe and the Far East was severed, providing a major impetus for the maritime exploration that would mark the new era. The use of cannons led to a change in how wars would be fought. The scholars who fled from the fall of the Empire into Italy helped to spark a new wave of thought and philosophy. The last of the great Old World empires had fallen, but in that death was a Renaissance for Europe. Cold comfort for the Byzantines, who would never rise again.

It is said that Mehmed, in his later years, visited Troy and claimed that he had “avenged it”, by conquering the Greeks – an ironic claim, given that the Byzantines claimed to be the Romans, and the Romans claimed descent from the Trojans. The Turks would go on to conquer all of Greece, and hold it until the 19^th century. As the body of Constantine XI was never recovered, a folk legend grew among the people of Greece that the “Marble Emperor” (as he became known) would one day return to lead them to freedom, and his name became a rallying cry in the Greek War of Independence. Greece would win freedom from the Turks, but Constantinople (nowadays called Istanbul) remains the capital of Turkey to this day. The Byzantine Empire had fallen forever. The last vestige of Rome was no more.