Mehmed II conquers Constantinople and ends the Byzantine Empire
A 21-year-old sultan drags warships overland to bypass a harbor chain, and Byzantium's eleven-century capital falls in 53 days.
Quick facts
- Sultan
- Mehmed II, "the Conqueror" (r. 1444-46, 1451-81)
- Siege began
- 6 February 1453
- City fell
- 29 May 1453
- Byzantine emperor
- Constantine XI Palaiologos (killed in the fighting)
What happened
Sultan Mehmed II opened the siege of Constantinople on 6 February 1453 after Byzantine Emperor Constantine XI refused an ultimatum to surrender. The city's Theodosian Walls were defended by only about 5,000-7,000 soldiers under the Genoese commander Giovanni Giustiniani, spread thin across a long perimeter, while Mehmed had new colossal cannons built specifically for the siege. When Byzantine ships blocked the Golden Horn with a giant chain, Mehmed had his fleet dragged overland on rollers to bypass it, a maneuver that let Ottoman ships attack the city's weaker sea walls. After a final assault launched in three waves on 29 May, regular infantry supported by artillery breached the outer wall and the city fell; Constantine XI died in the fighting. Mehmed's troops sacked the city for three days before the sultan made his triumphal entry through the Gate of Charisius.
Why it matters
The conquest ended the Byzantine Empire after more than a thousand years and gave the Ottomans a capital positioned to control trade between the Black Sea and the Mediterranean. Mehmed repopulated the depopulated city with people relocated from across Anatolia and the Balkans regardless of religion, and Constantinople, later known as Istanbul, remained the Ottoman capital for the rest of the empire's history.
How we know
World History Encyclopedia's biography of Mehmed II reconstructs the siege from the chronology of the naval blockade, the overland ship transfer, and the three-wave final assault, citing the standard Ottoman-studies bibliography on the conquest.
Sources
- World History Encyclopedia. Mehmed II · Reputable sourceworldhistory.org · The domain "worldhistory.org" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- World History Encyclopedia. Hagia Sophia · Reputable sourceworldhistory.org · The domain "worldhistory.org" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
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Related timelines
- The Byzantine Empire → · See the Byzantine Empire timeline for the full arc of the empire Mehmed II's conquest brought to an end.