The next part of the series.

CONSTANTINOPLE
February–May 1453

Forces Engaged
Turkish: 90,000 men. Commander: Sultan Mohammed II.
Byzantine: Less than 10,000 men. Commander: Emperor Constantine XI Paleologus.

Importance
This battle accomplished the final destruction of the Byzantine Empire and opened Europe to the spread of Islam. It also marked the arrival of the Ottoman Turks as the dominant Moslem faction until the twentieth century.
Historical Setting
When Constantine the Great established the city of Constantinople as his capital in 323, he occupied the former city of Byzantium, which had controlled for centuries the straits separating Asia and Europe. The Sea of Marmora is flanked northeast and southwest by the Bosporus and the Dardanelles, two narrow passages that link the Mediterranean and the Black Seas. Unless one plans to go completely around the Black Sea, the only way from Europe into Asia Minor is across one of those straits, and Byzantium/Constantinople/Istanbul has therefore been an extremely strategic possession for both land and naval warfare, as well as overland and maritime trade.
As Rome faded and Constantinople rose in power, Constantinople became the seat of the Eastern Roman, or Byzantine, Empire. It was not only the political capital of much of the Mediterranean and Middle East, it was the seat of the Greek Orthodox Church, rival to the power of the pope in Rome for the souls of Christians everywhere. In the end, it was the religious rather than political differences that spelled Constantinople’s doom.
In the seventh century, Mohammed the Prophet founded Islam. Claiming his divinely inspired teachings, the Koran, to be the successor to the Bible and the fulfillment of God’s plan for humanity, he oversaw the spread of his faith by both proselytization and warfare. By coincidence (or divine intervention) Mohammed arrived on the scene in Arabia just as the two major Middle Eastern powers, Persia and the Byzantine Empire, had fought each other to an exhausted standstill. Mohammed was therefore able to undertake a massive territorial acquisition hand in hand with the spread of his faith, and both Persia and the Byzantine Empire suffered major losses of real estate, as well as major losses of converts to Islam who found it less oppressive than the ultraconservative Orthodox Church.
For 700 years, the forces of Islam and Orthodoxy struggled against each other, with both sides trading ascendancy. By the fifteenth century, however, the Byzantine Empire had shrunk to almost nothing: Constantinople and a handful of Aegean islands. An earlier threat to the city by Islam had resulted in the Crusades in the twelfth century, but those too had ended in further alienation between the Catholic and Orthodox Churches. When in 1452 Sultan Mohammed II, son of Murad II, decided that Constantinople needed to be his, European response to pleas for help were almost entirely negative. England and France were just winding down their own costly Hundred Years’ War. Germanic and Spanish princes and kings hinted at aid but sent nothing. Only in Italy was there any positive reaction. Genoa and Venice did not want to see Constantinople fall into the hands of Arab merchants, and Rome promised aid if the Orthodox Church would submit to papal will. To save his city, Emperor Constantine XI Paleologus would make any bargain, so he agreed to Rome’s demand; it netted him a mere 200 archers for his meager defenses. Constantine’s decision was not a popular one among many Byzantines, who opined that they preferred Turkish domination to Roman.
In the spring of 1452, Mohammed II sent 1,000 masons to the Bosporus to begin construction of a fort with which to cover the transport of his men across the straits. Constantine could do little more than lodge a protest because he numbered among his citizens a mere 5,000 native and 2,000 foreign soldiers. He did, however, have tradition on his side, for the triple walls that blocked the city from the landward side had withstood twenty sieges in the city’s history, even though they were at this point not in the best of repair. He also had, as of January 1453, the services of the Italian soldier of fortune Giovanni Giustiniani, who arrived with 700 knights and archers. Giustiniani was well known in Europe for his talents in defending walled cities. Unfortunately, Mohammed also had some European assistance in the form of a cannon maker named Urban from Hungary, who provided the Moslem army with seventy cannon, including the “Basilica,” a cannon 27 feet long and firing stone balls weighing upward of 600 pounds. It could fire only seven times a day, but did significant damage to anything it struck, including the city walls.
The rest of Constantinople was defended by a single wall that ran the circumference of the city’s seaward sides. As Mohammed had chosen to cross his men to the north, across the Bosporus, the southern approach was open to the Mediterranean. The primary harbor inlet, called the Golden Horn, was protected by a chain boom across its mouth backed by twenty-six galleys. Thus, the route for relief was open, if indeed any would be forthcoming.
The Battle
Mohammed II arrived before Constantinople’s walls on 6 April 1453. He led 70,000 regular troops and 20,000 irregulars called Bashi-Bazouks, who were fighting only for the loot they might gain when and if the city fell. The premier troops were the Janissaries. These were slave soldiers taken captive in their youth from Christian families and raised in a military atmosphere to serve the sultans. They were heavily armored and highly skilled, and at Constantinople they were beginning to use personal firearms for the first time. Mohammed’s first act was to seize the town of Pera across the Golden Horn from Constantinople. At first it was little more than symbolic, but had serious ramifications later. He then arrayed his forces on the city’s western face and prepared for the siege. The northern end of the city was protected by a single wall, near the imperial palace. It was there, in a section called the Blachernae, that Constantine placed the greatest portion of his men.
On 18 April, Mohammed decided that the previous 12 days’ cannonade had softened up the defenses sufficiently for an assault. A narrow breach in the walls was easily defended, and the Byzantine troops killed 200 attackers and drove off the remainder without loss to themselves. On 20 April, lookouts on the seawall saw the sails of four ships approaching from the south, three Genoese transports with men and supplies from Rome and a Byzantine ship hauling corn from Sicily. After a hard fight with the Moslem fleet, they managed to break through, clear the boom, and enter the Golden Horn. Mohammed decided he had to control the harbor, but he could not pass the chain boom. He therefore ordered ships to be dragged overland, through the town of Pera, to the harbor. It was a monumental feat of engineering, and on 22 April, thirty Turkish ships were in the Golden Horn. The Byzantine counterattack was betrayed by an agent of the sulta managed to destroy only a single Turkish ship. In spite of this Turkish accomplishment, the presence of the ships in the Golden Horn had little effect on the siege.
Mohammed continued his cannonade against the walls, and by 6 May had opened another breach at the Gate of St. Romanus, where the Lycus River enters the city. Giustiniani, rather than trying to repair the wall under fire, instead built a new one just behind the breach. When the Turks attacked on 7 May, their 25,000 men were thrown back after 3 hours of fighting. On 12 May, another breach in the wall at the Blachernae was assaulted and only quick reinforcement by Constantine and the Imperial Guard was able to stem the tide. Mohammed then tried undermining the walls, but Constantine had on his staff Johannes Grant, who managed to locate each of the mining attempts and either undermine the mines or destroy the attackers inside with explosives, flooding, or the incendiary Greek fire. None of the fourteen mines succeeded in damaging any walls.

Mohammed then determined to try scaling the walls. He had a siege tower constructed and rolled into place before the Charisius Gate, the northernmost opening in the city walls. Bombardment had destroyed one of the defending towers in the walls, and the siege tower was able to provide covering fire for Turks filling in the moat before the wall. In desperation, Constantine called for volunteers for an attack
on the siege tower. It was unbelievable successful. Surprising the Turkish guards, the Byzantines broke pots of Greek fire on the wooden siege tower while their compatriots spent the night rebuilding the city wall and its destroyed tower. The next morning, Mohammed saw only the charred remains of his assault machine smoldering before the newly reconstructed tower in the city wall.
In both camps, officers argued the pros and cons of the siege. The defenders were exhausted and running our of supplies. In Mohammed’s camp, some factions were for ending the siege before a rumored rescue fleet could arrive. Instead, Mohammed favored those who counseled continuation, and the sultan decided on one more attempt before giving up. The most serious damage to the walls had been inflicted along the Lycus River entrance to the city, and it was there that he proposed to launch his final assault. A spy in the Turkish camp alerted Constantine to the plan, but could his dwindling force hold on for one more battle? The attack started at 0200 on 29 May with the Bashi-Bazouks hurling themselves against the Byzantine defenses. For 2 hours, the Byzantines killed them with arrows and firearms, but grew increasingly tired in the process. As soon as the first attack was repulsed, Mohammed threw in the second wave before the defenders could catch their breath. Even though these were regular troops with better discipline and equipment, the narrow breach provided the defenders with less area to cover, and they threw back that assault as well.
After another 2 hours of fighting, the Byzantine troops could barely stand, but they now had to face the third wave, made up of Janissaries. Fighting on adrenalin alone, Constantine’s troops repulsed them as well. As this was going on, however, a small band of Turks found a small open gate and rushed a handful of men through before it could be closed. When they seized a tower near the Blachernae and raised the sultan’s banner, the rumor quickly spread that the northern flank had been broken. Simultaneously, Giovanni Giustiniani was severely wounded. His evacuation badly hurt his men’s morale and, coupled with the report from the north quarter, the defenders began to fall back. Mohammed was quick to exploit his advantage. Another assault by fresh Janissaries cleared the space between the walls and seized the Adrianople Gate, through which the attackers began to pour.
After another 2 hours of fighting, the Byzantine troops could barely stand, but they now had to face the third wave, made up of Janissaries. Fighting on adrenalin alone, Constantine’s troops repulsed them as well. As this was going on, however, a small band of Turks found a small open gate and rushed a handful of men through before it could be closed. When they seized a tower near the Blachernae and raised the sultan’s banner, the rumor quickly spread that the northern flank had been broken. Simultaneously, Giovanni Giustiniani was severely wounded. His evacuation badly hurt his men’s morale and, coupled with the report from the north quarter, the defenders began to fall back. Mohammed was quick to exploit his advantage. Another assault by fresh Janissaries cleared the space between the walls and seized the Adrianople Gate, through which the attackers began to pour.
Results
Constantine XI led his last remaining troops into the Turkish onslaught and died for his city and empire. He was joined by almost all his co-defenders as well as a huge portion of the civilian population, for the Turks went on a rampage, looting Constantinople. Mohammed II limited very little of the pillage, reserving the best buildings for himself and banning their destruction. He appropriated the Church of St. Sophia, and within a week the Hagia Sophia was hosting Moslem services. The Turkish flags flying over the city were seen by the thirty ships of a Venetian fleet sailing to Constantine’s relief, which turned around and sailed home.
The looting finally subsided, and the bulk of the population that was not killed was enslaved, possibly numbering 50,000 people. The bastion of eastern Christianity, which had stood against all opponents, fell after more than 1,100 years as Constantine the Great’s city. For Mohammed II, it was merely another step in the expansion of his domain, for he proceeded

to conquer Greece and most of the Balkans during the remaining 28 years of his reign.
Western Europe, which had done so little to assist Constantinople and the remnants of the Byzantine Empire, was shocked that it fell after so many centuries of standing fast against everyone. In Rome, the Catholic Church was dismayed that they would now have no eastern Christians to convert, as they were all rapidly becoming Moslem. The Eastern Orthodox Church did survive, however, because Mohammed allowed a patriarch, George Scholarius, to preside over the church. It remained, therefore, a viable religion, but now far from the reach of the Catholic Church’s influence. As such, its survival heartened others who chafed under the pope’s rule. Within 60 years, Martin Luther was leading a major protest against the Roman Catholic Church. That protest started the Reformation.
The trading centers of Genoa and Venice quaked at the thought of having to deal with the hard-bargaining Arab merchants that now completely controlled all products coming from the Far East. The major cities of eastern Europe began to fear the Turkish armies approaching their gates, and for the next 450 years Austria in particular carried on a constant struggle with the Ottoman Empire. The Ottoman Turks, who had been slowly establishing themselves as the premier Middle Eastern Moslem power, now held that title firmly and controlled at their height almost as much as the Byzantine Empire had: the Balkans, the Middle East, and much of North Africa. They also exercised naval control of the eastern Mediterranean until 1571, when Christian naval forces won the battle of Lepanto.
Still, all was not negative for western Europe. The flood of refugees from southeastern Europe, especially Greece, brought thousands of scholars to Italy, further enhancing the peninsula’s Renaissance. Italian merchants, shocked at the exorbitant prices that the Moslems charged as dealers for spices and silks from the east, soon began to search for other ways to get those goods. Within 30 years, Portuguese ships were exploring the coast of Africa for ways to India and China, and the Genoese captain Christopher Columbus soon thereafter convinced the Spanish monarchy to finance his dream of establishing a new trade route to the east. Certainly the age of European exploration came much sooner because of Constantinople’s fall.
References:
Antonucci, Michael. “Siege without Reprieve,” Military History9(1), April 1992; Durant, Will. The Reformation. New York: Simon & Schuster, 1957; Fuller, J. F. C. A Military History of the Western World, vol.1. New York: Funk & Wagnalls, 1954; Norwich, John J. Byzantium: The Decline and Fall. London: Viking, 1995; Runciman, Sir Steven. The Fall of Constantinople—1453. Cambridge, UK: University of Cambridge Press, 1968 [1903].