The siege of Constantinople commenced in April 1453, as Sultan Mehmed II, also known as Mehmed the Conqueror, sought to capture the historic city which had stood as a bastion of Christianity and the Byzantine Empire for over a thousand years. The Byzantine defenders, led by Emperor Constantine XI, prepared for an intense confrontation against the formidable Ottoman forces, which were estimated to be around 80,000 strong. The Ottomans made use of innovative military technology, notably large cannons developed by the Hungarian engineer Urban. These cannons played a crucial role in breaching the city's famed walls, which had withstood numerous sieges over the centuries.

As the siege progressed, the defenders’ supplies dwindled and they faced not only the numerical superiority of the Ottomans but also the psychological pressure of an impending defeat. On May 29, after weeks of bombardment, the Ottomans launched a final assault, penetrating the walls and storming into the city. The Byzantine forces could not hold back the overwhelming numbers, and the city fell into Ottoman hands. Such an event forever changed the socio-political landscape of the region, as Constantinople became the new capital of the Ottoman Empire, leading to a significant shift in power from the Byzantine to the Ottoman authority.

The fall was marked by a fierce battle within the city, resulting in significant casualties among the citizens and defenders alike. After the conquest, Mehmed II implemented policies to repopulate the city, inviting various ethnicities and encouraging trade, thus preserving and transforming its rich heritage into a center of commerce and culture within the Ottoman Empire. The event signified not just the end of the Byzantine Empire, but it was also seen as the culmination of centuries of Islamic expansion and a turning point for both the Christian and Muslim worlds, influencing travel, trade, and diplomacy in the centuries to follow.