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The Mongols burned the legendary library first. Thousands of manuscripts on astr
1256 Event

December 15

Hulagu Khan Destroys the Assassins' Fortress at Alamut

The Mongols burned the legendary library first. Thousands of manuscripts on astronomy, mathematics, philosophy—gone in hours. Hulagu Khan wasn't just conquering the Assassins' mountain fortress. He was erasing their intellectual legacy. The Hashshashin had ruled through fear for 166 years, their agents infiltrating courts across the Islamic world. Alamut seemed impregnable, perched 6,000 feet up in the Alborz Mountains. But the garrison surrendered after a single week of siege, their grand master already captured. Hulagu executed him anyway. Within months, every Nizari Ismaili castle in Persia fell. The sect that had terrified sultans and caliphs simply vanished from the historical stage.

December 15, 1256

770 years ago

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