1256
Hulagu destroys the Assassin strongholds
The Mongol army besieged and captured the mountain fastnesses of the Nizari Ismailis, including the legendary Alamut with its library and gardens. Their grand master surrendered and was later murdered. The sect that had terrorized sultans and caliphs for a century was crushed. The Assassins' network of mountain fortresses, which had seemed impregnable for generations, fell one by one to Hulagu's Chinese siege engineers.
Possible supernova observed by multiple cultures
Astronomers in several regions recorded the appearance of a bright new star visible in daylight for weeks. Chinese court astronomers, Arab observers, and possibly Japanese monks noted the phenomenon, which modern astrophysicists have tentatively linked to the formation of the Crab Nebula's remnants, though the dating remains debated. The fact that multiple civilizations documented the same celestial event illustrates the era's interconnected astronomical traditions.
Hulagu founds the Ilkhanate
Having taken Alamut from the Assassins, Hulagu declared himself Ilkhan, subordinate khan, of the Mongol territories in Persia and Mesopotamia. The new Ilkhanate would administer Iran for nearly a century and become a vector for Chinese-Persian cultural exchange. Under Mongol patronage, Persian miniature painting absorbed Chinese techniques, creating a new visual language that would flower into the masterpieces of Timurid and Safavid art.
Nasir al-Din Tusi builds the Maragheh observatory
Under Hulagu's patronage, the Persian polymath Nasir al-Din Tusi established an astronomical observatory at Maragheh in Azerbaijan, equipped with massive instruments and a library of four hundred thousand volumes. His planetary models, correcting Ptolemy, would influence Copernicus two centuries later through channels still debated by historians. The observatory attracted scholars from China, Byzantium, and the Islamic west, making it history's first international research institution.