Constantinople was the capital of the Byzantine Empire from the 4th century to 1453. During this period, it became one of the largest and most prosperous cities of Europe and a hub of cultural activity.
Towards the later centuries of the Empire, this changed as the city frequently suffered at the hands of invaders, most notably at the hands of Crusaders in early 13th century. This led to a decline in the significance of the city which ultimately could not withstand the attack of the Ottomans in 1453. After a seven-week siege, the city fell to the Ottomans.
From 13th century onwards, the grand city of Constantinople which was once the cultural heart of Eastern Europe had been on a steady decline. In 1204, forces of the Fourth Crusade ravaged the city and included it in the establishment of a Latin state.
In 1261, the city returned to the Byzantines but had to continuously withstand the attacks of many enemies, including the Bulgars and the Turks. This was compounded by the outbreak of plague in 1346 which killed off most of the city’s population. By the time the Ottoman Turks laid siege to the city in 1453, the Byzantine Empire was exhausted and had little power to defend the city.
The siege of the capital city was laid by Ottoman Sultan Mehmed II. Mehmed II first reinforced the Ottoman rule in the neighbouring regions and then marched on Constantinople with a sizable land and sea force. He first had the fortifications outside the city taken over so as to mitigate any threats. During the siege, the Ottomans attempted to take the city by force and repeatedly attacked it. But most of these attacks were successfully repulsed.
In May, Mehmed II finally launched a decisive assault which helped the Ottomans break into the city despite significant losses. The conquest was followed by large-scale looting and plundering of the city which continued for three days. Only monumental architecture and other notable structures were secured against plunder by the decree of the Sultan. According to historical estimates, tens of thousands of citizens were killed following the conquest.
The fall of the city of Constantinople effectively marked the end of the Byzantine Empire. The Empire had existed since the 4th century to 15th century and was the true successor to Roman Empire as well as the most important Christianity polity in Eastern Europe for many centuries.
The fall of the city marked the end of this era of Byzantine power and ushered in a new era of Ottoman power. Although there were stirrings in Western Europe over the fall of Constantinople and the Papacy attempted to raise the flag of another Crusade to retake the city, none of these efforts bore any fruit.
The city thus conclusively remained within Ottoman hands and remains a part of the Turkish territories to this day. The fall of the city also sent waves of Byzantine emigrants to different parts of Western Europe where they became the key motivators of the European Renaissance.