The Nizari Ismaili Imamate

The Nizari Ismaili branch of Shia Islam holds, like Twelver Shia Islam, that leadership passed through a designated line of Imams descended from Ali and Fatimah, but the Nizari line has never gone into occultation: it continues today in an unbroken, publicly known succession. The Ismaili line traces through the Fatimid caliphate, which ruled Egypt and much of North Africa and the Levant from 909 to 1171 CE and combined the caliphate, the office of political ruler over the Muslim community, with the Ismaili imamate. A succession dispute in 1094 split Ismailism into Nizari and Mustaali branches; the Nizaris, based for a time at the mountain fortress of Alamut in Persia, continued their own line of Imams independent of the Fatimid state after its fall.

Following the destruction of the Nizari power base at Alamut by the Mongols in 1256, the Imams lived for centuries in relative obscurity in Persia. The line re-emerged into wider prominence in the nineteenth century when Imam Hasan Ali Shah was granted the honorific title Aga Khan by the Qajar Shah of Persia, a title his successors have carried since; his descendants later relocated the seat of the imamate first to India and then internationally.