In the year 654/1256, the Mongol "Ilkhan" surrounded the Persian "fida'i" stronghold at Alamut, the headquarters of the movement, resulting in a brutal massacre of the Ismailis and widely believed to mark the end of their influence in this region. However, after investigation of various historical sources, we learn that the Nizari Ismaili influence survived, and a son of the Imam Rukn al-Din Khwarshah even managed to re-capture Alamut in 674/1275. Though his own residence at Alamut would not last, there is some evidence that the Imam Islam Shah returned to live at the fort of Alamut itself. It would not be until 819/1416, after a massacre at the hands of Amir Kiya’i "sayyid" Radi Kiya, that the Imams would abandon this region.