Möngke Khan
In 19 November 1256, the Nizari Imam, who was in the Maymun-Dizh, surrendered the castle to the besieging Mongols under Hulagu Khan after a fierce conflict. Alamut fell in December 1256 and Lambsar fell in 1257, with Gerdkuh remaining unconquered. In the same year, Möngke Khan, the khagan of the Mongol Empire, ordered a massacre of all Nizari Ismailis of Persia. Rukn al-Din Khurshah himself, who had traveled to Mongolia to meet Möngke Khan, was killed by his personal Mongol guard there. Gerdkuh castle finally fell in 1270, becoming the last Nizari stronghold in Persia to be conquered.