When the last Roman emperor saw his city falling in 1453, he tore off his imperial regalia, charged into the Ottoman army on foot — and was never seen again.
On May 29, 1453, after a 53-day siege, Ottoman Sultan Mehmed II — just 21 years old — captured Constantinople and ended the Byzantine Empire. What he was actually ending was far older: the Eastern Roman Empire had been the unbroken continuation of the Roman state since Augustus Caesar, surviving for 1,500 years while the Western Empire had collapsed a thousand years earlier.
The city's legendary defensive walls — the Theodosian Walls, 800 years old and considered the most formidable fortifications in the world — were breached by something they had never faced before: gunpowder artillery. Mehmed had commissioned a Hungarian engineer named Orban to build a cannon 27 feet long that fired 600-pound stone balls. The walls that had repelled dozens of sieges crumbled under the bombardment.
The disparity of forces was staggering. Mehmed commanded somewhere between 50,000 and 80,000 soldiers and 110 ships. The Byzantine defenders, led by Emperor Constantine XI, could muster only about 7,000 men and 26 ships — fewer soldiers than a modern infantry division defending one of the world's greatest cities.
One of the decisive moments of the siege came from an unlocked door. When the final Ottoman assault began before dawn on May 29, a small postern gate in the Blachernae walls — the Kerkoporta — had been left open by a raiding party that had failed to secure it on their return. Ottoman soldiers poured through. Panic spread through the defenders, and the line collapsed.
The last Byzantine emperor, Constantine XI Palaiologos, reportedly tore off the purple insignia of his imperial office when he saw the city was lost, so he would not be identifiable as the emperor, and charged into the fighting on foot. His body was never definitively found — only identified later by the golden eagles embroidered on his boots among a pile of the dead.
The fall sent shockwaves across Europe. Constantinople had been the guardian of the eastern Mediterranean, the repository of ancient Greek and Roman learning, and a major trading hub. Thousands of Greek scholars fled westward, carrying manuscripts and knowledge that would help fuel the Italian Renaissance. The Ottoman conquest also disrupted the overland Silk Road trade routes to Asia — one of the pressures that pushed European powers to seek sea routes around Africa and, ultimately, across the Atlantic.
Mehmed II, known thereafter as 'the Conqueror,' made Constantinople his new imperial capital, renaming it Istanbul. He was 21 years old. He went on to rule for another 28 years, expanding the Ottoman Empire further into Europe and Asia, and is considered one of the most consequential rulers of the 15th century.