9. Hulagu Ends the Abbasid Caliphate
After settling the Assassins’ hash, Hulagu turned his attention to the Abbasid Caliphate. When the Caliph refused to submit, Hulagu invaded, besieged him in Baghdad, and captured the city in 1258. Hulagu then destroyed the city along with all its treasures, such as the Grand Library of Baghdad, and massacred between 200,000 to a million inhabitants. To avoid a Mongol taboo against spilling royal blood, the captured Caliph was executed by being rolled into a carpet, which was then trampled by Mongol horses riding over it. That ended the Abbasids, and the Islamic institution of the Caliphate. Hulagu then conquered Syria, bringing to an end the Ayubbid dynasty founded by Saladin.
He then set his eyes on Egypt, but on the eve of invasion, he received word that his brother Mongke had died. As a potential successor, Hulagu returned to Mongolia, and in his absence, the Mongols he left behind under a trusted subordinate were wiped out by the Egyptian Mameluks at the Battle of Ain Jalut in 1260. It was the first major defeat of a Mongol army, and it broke the spell of Mongol invincibility. Hulagu was not selected to succeed his brother as Great Khan, so he returned west to avenge the defeat at Ain Jalut. Instead, he ended up warring with a cousin, Berke, who had succeeded to the leadership of the Golden Horde, converted to Islam, and was enraged by Hulagu’s rampage in the Muslim world. The war with Berke was Hulagu’s main focus for the remainder of his life, until his death in 1265.