Muhammad ibn Buzurg-UmmidMuḥammad ibn Buzurg-Ummīd was the son of Kiyā Buzurg-Ummīd, and the third ruler of the Nizari Ismailis from 1138 until 1162 based in Alamut.CareerUpon the demise of Kiyā Buzurg-Ummīd on February 9, 1138, he was appointed as the commander of Alamut Castle by the third concealed Imam Hasan Al-Qāhir ibn Al-Muḥammad of the Nizārī Ismā'īlī state. He died in 1162 and was succeeded by his son Hassan as dai. Some, including authoritative historian Joveyni, claim that it was his son who declared himself imam as Hasan ‘Alā Dhīkr‘īhī's-Salām, de facto usurping the Nizari Imamate. Nizari sources generally claim that the two individuals are distinct.