Ali ibn Abi Talib was acclaimed in 656 CE as the fourth caliph after the death of the Islamic prophet Muhammad. Following the 656 assassination of the third caliph Uthman in Medina by provincial rebels who had grievances about injustice and corruption, the prophet's cousin and son-in-law was elected to the caliphate by the rebels, the Ansar (early Medinan Muslims), and the Muhajirun (early Meccan Muslims). While the election of Ali faced little opposition, his support was limited among the Quraysh, some of whom aspired to the caliphate. The Umayyads (Uthman's tribesmen) and some others thereby left Medina––some thus breaking their oaths of allegiance––and soon rebelled against Ali.
