History
Ali is the central figure at the origin of the Shia / Sunni split which occurred in the decades immediately following the death of the Prophet in 632. Sunnis regard Ali as the fourth and last of the "rightly guided caliphs" (successors to Mohammed (pbuh) as leader of the Muslims) following on from Abu Bakr 632-634, Umar 634-644 and Uthman 644-656. Shias feel that Ali should have been the first caliph and that the caliphate should pass down only to direct descendants of Mohammed (pbuh) via Ali and Fatima, They often refer to themselves as ahl al bayt or "people of the house"
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When Uthman was murdered while at prayer, Ali finally succeeded to the caliphate.
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