The Empire did not end with the Sack of Constantinople in 1204, but it was the beginning of the end. Crippled by the loss of its capital city and much of its land, it fragmented into four separate kingdoms, in Anatolia, Thessalonica, Epirus and the Morea (the Peloponnese). The Crusaders' new 'Latin Empire' was short-lived, and the Anatolian Byzantines recovered the city in 1261, but they now had the task of trying to reunite the four kingdoms - the resulting civil wars wore out the resources of the Empire. In addition, much of the land that had been owned by Byzantium now lay in the hands of the Franks and Venetians. It was a greatly reduced Byzantine Empire that limped along for the next 200 years or so.

The Black Death hit Constantinople in 1347 and killed nearly 90% of the population. Then in 1354, an earthquake occurred, damaging many of the buildings. In this period, also, a new threat arrived from the east: the Ottoman Turks. Byzantium had already encountered their cousins, the Seljuk Turks in around 1000 AD, but the Seljuks had been annihilated from behind by an invasion of Mongol hordes. Now the Ottomans were gradually encroaching on Byzantine territory, taking Anatolia (the Asian part of what is now Turkey), then crossing over into Europe and taking Thrace (the European part) as well. The Ottomans made their capital in Edirne, which formerly had been the Byzantine city of Adrianople.

The people had always considered themselves under the personal protection of the Virgin Mary, the mother of Jesus Christ. Now it appeared that that protection had been withdrawn.

The Last Emperor

Constantine XI Palaeologos was the last Emperor. On him fell the burden of leading the last defence of the city. He inherited the throne from his brother, John VIII Palaeologos, who died without a child. By the time Constantine received the purple in 1449, the Empire was reduced to a sorry state. Constantinople still had good defensive walls and a well-defended port, but the population was reduced to about 50,000, and of those less than 7,000 were fit for fighting. Outside of the city, there were now no lands at all, although the Empire still owned and had a free sea passage to the Morea (the Peloponnese) in Southern Greece. It was a far cry from the days when the Roman Empire stretched from the Persian Border to the Atlantic Ocean.

The Siege

In 1453, the Ottoman Turks decided to invade the city. Their ruler, Sultan Mehmet II, was a highly educated but cruel and ruthless tyrant. Stories about him abound. One is that when his father died, he rushed to the palace. His father's widow came to congratulate him on his new position as Sultan. He greeted her warmly. When she returned to her quarters, she found that her infant son, who she had left in the bath, had been murdered under Mehmet's orders as a potential future threat to his throne.

Although Mehmet's father had been happy to leave Byzantium as an isolated Greek city in the middle of his lands, Mehmet wanted to take the city. He waited until 1453 because he had a secret weapon: two big guns. These enormous cannons were intended for the destruction of the land walls - they could only be fired once every few hours, but could wreak enormous damage. The bigger of the two guns, which was probably the biggest cannon ever built, could fire a projectile weighing 1,450 pounds (660kg) a distance of more than a mile (1.6km). Mehmet also assembled about 100,000 troops for the taking of the city. It was obvious from the start that the force of less than 7,000 inside the city could not fight against these odds, but the defences of the city were so good that they just might be able to sit tight and wait it out until help arrived from the West. It is no trivial task to keep a force of 100,000 men in the field - providing food and water and keeping the camps clean and free from disease is a huge undertaking. Mehmet was willing to pay the price, but staked his reputation on success. He reckoned that the West would be slow to send help - nobody in the West believed he could succeed. He was right; no help came. Instead the Byzantines put their trust in the Christian God, who they thought would provide them with a miraculous escape. Again, no help came.

On 5 April, 1453, Mehmet stood outside the city and issued the offer of peace required by Muslim law - the inhabitants could surrender now and no harm would befall them. He was ignored.

On 6 April, he started his attack on the city using the cannons. These blasted away at the land walls, concentrating on the area around the St Romanus Gate, where the land outside sloped down to the walls, giving the cannons the advantage of height. Eventually, they managed to knock a hole in the outer wall. But the Byzantines inside were there to repair the damage. They built a huge stockade from earth, barrels filled with earth and any wood they could find from inside the city, and filled in the hole in the wall. The stockade was undoubtedly a weak spot in the defences, but it was even more resistant to cannon fire than the walls, as the earth absorbed the impact of the cannon balls. The assault on the walls went on for more than a month, stretching the resources of the Turkish army to the limit. At this stage, Mehmet realised he was running out of time. He would have to go for an all-out attack, occupying the Byzantines on all fronts, which would force them to spread out their defensive forces.

He ordered his troops to completely surround the city, by land and sea. He had assembled a fleet of more than 300 ships which looked very impressive, but most of these were not warships; they were troop carriers and supply ships. The Turks were not great sailors, having come originally from Central Asia, far from any ocean. The Byzantines had only a few ships themselves, but they were supplemented by ships belonging to the Genoan and Venetian trading communities in the city.

Nevertheless, the Byzantine fleet was effectively powerless - there were just too many enemy ships. The fleet stayed safely in the harbour, guarding the northern side of city.

The Taking of the Harbour

Byzantium was roughly triangular in shape. The west side was defended by the four miles of the mighty Land Walls of Theodosius, which had never been breached in more than a thousand years of history. On the south side of the city, the sea walls looked straight onto the deep and treacherous waters of the Sea of Marmara. The strong currents here effectively protected the city from any attack by sea. The north side of the triangle was a potential weak spot, in that it opened onto the narrow inlet of the Golden Horn, which was the harbour of the city. It was here that the Crusaders had broken into the city in 1204, so it was considered to be the weakest point in the city's defences. The harbour was protected by a mighty chain which could be stretched across the mouth of the inlet. This effectively prevented the Turkish fleet from attacking from this side. An attempt to break the chain by ramming it had reduced one of the Turkish ships to matchwood.

Mehmet came up with the daring idea of carrying 80 of his ships over land to the west end of the Golden Horn. This meant that the Byzantine fleet could be attacked from the back and pushed eastwards, thereby exposing the north side of the city. He did this by laying down a plank road from the Bosphorus around the north side of the hill of Galata to the west end of the Golden Horn, a distance of a few miles. The planks were greased with lard, and the Turkish fleet was dragged along on rollers on this makeshift slideway to the inner harbour.

Once the inner harbour was secured, the Turks built a floating bridge across the inlet, from barrels with planks tied across the top. In the middle of the bridge they mounted a cannon which prevented the trapped Byzantine fleet from approaching. The Turks now effectively had the city surrounded on all sides.

The Eve of the Battle

The Turks made no attempt at this stage to conceal their plans. It was announced that they would attack the city in two days' time. The following day, Mehmet spent his time inspecting his troops and making sure everything was ready.

Inside the walls, Constantine walked the length of the land walls, checking that everything was as ready as it could be. The people of Constantinople, other than those guarding the walls, spontaneously assembled in Hagia Sophia, the church which was the cultural centre of the city, and prayed one last time for a miracle.

The Attack

The attack on the city took place in the early hours of Tuesday, 29 May, 1453. It came from all sides, and was unrelenting. There was a continuous stream of attackers hurling themselves against the walls from all sides, with guns, catapults, siege ladders and battering rams. Under this storm of attack, the city's defences finally gave way in a few places. One group managed to secure a tower in the northwest of the city and planted an Ottoman flag there, but they were unable to go any further into the city.

The breakthrough came at the stockade. Here the biggest collection of defenders, both Byzantines and Genoese, were assembled, led by Constantine himself and the Genoese leader, Giovanni Giustiniani. The defenders were in the area between the stockade and the inner wall. There was a small doorway in the inner wall, and Constantine had taken the precaution of locking it. In the heat of battle, Giustiniani was struck by a missile and badly injured. He asked for permission to unlock the door and go into the city to seek treatment for his wound. Constantine reluctantly let him go. When the Genoans saw their leader leaving the battle, they fled after him, leaving only the Byzantines to defend the stockade. The Turks noticed the sudden reduction in the number of defenders and picked this moment to attack, overrunning the stockade. The defenders tried to flee through the small doorway, but couldn't get through fast enough, and were slaughtered by the Turks. Some Turkish soldiers now entered the city through the door and opened the main gates of the city from the inside. The Turkish army poured in and the city was taken.

The Death of the Emperor

What happened to Constantine is unclear. He was last seen alive in the group between the wall and the stockade. He was probably killed in the attack, but no body dressed in the imperial purple was found there. He may have changed his clothes and dressed as a common soldier, a wise precaution considering that the Turks would undoubtedly want to capture him and bring him to the Sultan. The Turks found a body and brought it to Mehmet, where some Greeks confirmed that it was Constantine. The head was cut off and paraded around the city as Constantine's head, but there is some doubt as to whether it actually was or not.

Stories about Constantine's last moments abound and various versions of his last words are related by people who weren't there at the time. The fact is we don't know, but it seems likely that he died at the front, fighting for his city. Nobody around him survived to relate the final moments of the last Emperor.

The Aftermath

Once the Turks were inside the walls, the defenders gave no further thought to defense. The city had fallen. The looting and pillaging started. Women and children were raped or slaughtered on the spot. Those remaining Greeks who were not killed were rounded up as slaves and led out of the city. Mehmet rode into the city and stopped at Hagia Sophia, where he ordered that the Muslim call to prayer should ring out from the grand pulpit. From that time onward, the great church was a mosque.

Mehmet returned in triumph to Adrianople, but quickly organised the move of his capital to Byzantium. A new palace (the Topkapi) was built on an unused piece of ground beside Hagia Sophia. The walls which had been heavily damaged by cannon fire during the siege were rebuilt. He now had the perfect city from which to rule his Empire.

The Byzantine Empire was no more. The Ottoman Empire had begun.