The Western Roman Empire fell in 476 AD, when Germanic warlord Odoacer deposed the last Emperor, Romulus Augustulus, and sent back the imperial symbols to Constantinople. The Eastern Empire survived more or less intact until the beginning of the 7th century when they lost most of their Asian provinces first to the Persians, but Emperor Heraclius was able to recover these thanks to his brilliant campaigns in the 620s.
Then came the Arabs, who were just united under the banner of Islam. The Byzantines lost Syrian, the Levant, Byzantine Mesopotamia and Egypt to the Arabs, and there was no recovery. The empire survived the disasters of the 7th century, but never again became as powerful as it used to be.
Still, up until the disastrous Byzantine defeat at the Battle of Manzikert the Byzantines controlled Anatolia, most of the Balkans and parts of southern Italy. Things changed after the defeat at Manzikert, which allowed the Seljuk Turks to overrun most of central Anatolia. Thanks to the efforts of the Kommenos dynasty, the Crusades and the fracturing Seljuk Empire the Byzantines retook parts of Anatolia, and most of the coasts, but the interior remained mostly under Turkic control.
The Byzantines remained a strong regional power until the Fourth Crusade, but the sack of Constantinople in 1204 and the partition of the empire among the Crusaders was a disaster from which they never recovered. Although the Greeks succeeded in retaking their capital in 1261, the damage was already done. Civil Wars in the 14th century further weakened the Byzantine position, and by the late 14th century the territory of the empire consisted of little more than Constantinople and a few bits of territories scattered around the Balkans and Greece.
Simultaneously to the decline of the Byzantines rose the Ottoman Turks. Starting from a modest background, the House of Osman rapidly expanded in the 14th century to control most of Western Anatolia and the Balkans. Bayazid was already trying to capture Constantinople, but his catastrophic defeat against Timur halted his attacks and threw the Ottoman Empire into Civil War. Bayazid was captured by Timur, and his sons fought against one another for a decade. The empire made a recovery under the rule of Mehmed and Murad II.
Murad II died in 1451 and was followed on the throne by his young son Mehmed. Mehmed had already been Sultan when his father abdicated in 1444, but the Grand Vizier of the empire, Candarli Hallil pasha, deposed Mehmed in 1446 to recall his father.
Mehmed harboured resentment for the actions of Candarli Hallil, but the Grand Vizier was too influential to get rid of in 1451.
Mehmed was a very ambitious young man and he wanted to conquer Constantinople. In the first year and a bit of his reign, he began the preparations to besiege the city. He ordered the construction of another fort across the Bosphorus to block access to Constantinople. He also ordered raids into Greece, to frighten the brothers of Emperor Constantine XI.
Constantine threatened to release Orhan, a member of the Ottoman dynasty, to incite revolt in the Ottoman Empire. Mehmed was unfazed by the threats of the Greeks and he even had two of the Emperor’s envoys executed.
If Constantine had any doubts about the intentions of Mehmed, these were probably gone after the incident. He sent envoys to the Christian courts of Europe and even to the Pope, pleading for support. He received some reinforcements from the Italian Republics. The Italian reinforcements were not very numerous, but, led by the seasoned mercenary Giovanni Gustiniani, these forces were battle-hardened mercenaries.
The Byzantines strengthened the defences of their city as well as they were able to. The triple land walls of Constantinople were still a formidable obstacle for any invading force, while the chain across the Golden Horn blocked access to parts of the sea walls of the city.
By this time Constantinople was no longer the huge city of the earlier medieval period, as the Black Death and the decline of the empire made it impossible to maintain a city of several hundred thousand of inhabitants. Most historians estimate that the city had between 50,000-and 75,000 inhabitants when the Ottomans besieged Constantinople in 1453. The lower number of inhabitants was not a disadvantage during a siege, as the food supplies could last longer.
Estimates vary about the size of the opposing forces, but historians estimate that the defenders had around 10,000 soldiers at the highest count, plus whatever citizen militia and volunteers joined the soldiers on the wall. The Ottomans, on the other hand, had an army of somewhere between 60,000-100,000 soldiers. The Ottoman fleet also vastly outnumbered the fleet of the defenders, but so long as the chain blocked access for the Ottomans, this numerical disadvantage counted for little.
The young Sultan gathered a very impressive host for the Medieval period, but he knew that he will need all the soldiers he could muster to overwhelm the formidable walls of Constantinople.
The Siege Began
The siege began on April 6, 1453. The Ottomans blockaded the city with their fleet, while the army began the assault on the walls. The first task of the Ottoman army was to fill up the ditch that defended the city. This was not easy, as the defenders were constantly firing missiles and stones at the Ottoman soldiers who were filling the ditch. While his soldiers were working tirelessly to fill the ditch Mehmed ordered his artillery train to bombard the walls of the city. The walls were heavily damaged by the constant barrage, but Gustiniani constantly pushed his troops to fill the holes and repair the damaged parts. Gustiniani was also a very proactive commander, and constantly lead sorties out of the city to disrupt the siege works of the Ottomans. These sorties were often very successful and Gustiniani managed to destroy even Ottoman siege towers, but at the same time costly in terms of lives, lives which the vastly outnumbered defenders were ill-equipped to replace.
A small fleet of Genoese ships managed to break through the Ottoman blockade in late April to enter the harbour. The Genoese success infuriated Mehmed, who later publicly humiliated Admiral Baltoghlu.
As the days and weeks passed the Ottomans slowly filled up the ditch and were able to launch direct assaults on the walls. Their attacks were repelled, but the defenders also suffered heavy losses in their efforts.
Mehmed had other aces up his sleeve also. He ordered his troops to carry some part of the fleet overland to bypass the chain across the Golden Horn. This way the Ottoman fleet was deployed right under the sea walls of the city, forcing the already dwindling defender force to further weaken their numbers at the main wall.
Ottoman miners also tirelessly worked to place explosives under the walls, but the Byzantines had their countermeasures that kept the Ottoman miners in check.
The heavy losses the Ottomans suffered caused discord in the Ottoman camp, and the Grand Vizier urged the Sultan to make peace with the emperor. The Sultan was having none of it, and prepared his troops for a final assault.
The final assault came on May 29, 1453. Mehmed sent the soldiers of his vassals in the first wave of the attack, but these were quickly repulsed. The second wave was made up of the provincial troops of the empire, but these were also repelled. The final wave of the attack was made up of Mehmed’s veterans and household troops, and these troops finally succeeded in achieving a breakthrough. The commander of the defenders, Gustiniani, was gravely injured in the final assault and had to be carried to his ship. The loss of the valiant commander was a heavy blow, but the fate of the city was sealed when the Ottomans found an open sally port. Whether this was left open by mistake or was opened by traitors is anybody’s guess, but the Ottoman soldiers who entered there were able to overwhelm the defenders at a gate and open it for their comrades.
The attackers swamped in the city through the open gate and rapidly overwhelmed the defenders. As customary, the Ottoman troops were allowed to loot the city for three days before Mehmed ordered them to stop their rampage.
It is believed that around 30,000 of the city's inhabitants became slaves in the aftermath of the fall. Mehmed had grand plans for Constantinople and moved the seat of his capital there, a function which it served until 1922 when the Ottoman Empire was abolished.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2022 Andrew Szekler