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How did Mehmed II prepare to conquer Constantinople?
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Ottoman Empire
Map showing the expansion of the Ottoman Empire from about 1300 to 1700. The empire reached its greatest extent between 1683 and 1699.
To prepare for the conquest of Constantinople, Mehmed II undertook extensive diplomatic and military measures to ensure success:
- Diplomacy: He secured his flanks by signing peace treaties with Hungary and Venice to keep them neutral during the campaign.12
- Fortification: In 1452, he constructed the Rumelihisarı (Boğazkesen) fortress at the narrowest point of the Bosporus. This allowed him to restrict maritime passage between the Black Sea and the Mediterranean.12
- Military Technology: Mehmed commissioned the Hungarian gunsmith Urban to cast massive cannons, including pieces of a size previously unknown in Europe, specifically designed to breach the city’s formidable walls.12
- Naval and Land Forces: He built a fleet of 31 galleys and assembled large regiments from Rumelia and Anatolia. By early 1453, he had seized Byzantine coastal settlements to effectively isolate the capital before the final siege began.132
These preparations allowed Mehmed to systematically encircle the city and maintain a relentless artillery bombardment until the walls were finally breached.3