same time, Ali turned down proposals to advance his claims by force, possibly for the unity of a nascent Islam. Attack on Ali's house and his pledge While there is considerable uncertainty about the events, Ali most likely did not pledge allegiance to Abu Bakr until his wife Fatima died within six months of his father Muhammad, as reported by some canonical Sunni works. In Shia sources, the death (and miscarriage) of the young Fatima are attributed to an attack on her house to subdue Ali at the order of Abu Bakr. Sunnis categorically reject these allegations. After Fatima's death and in the absence of popular support, Ali is said to have relinquished his claims to the caliphate for the sake of the unity of a nascent Islam, which was facing internal and external threats, according to Mavani. In contrast with Muhammad's lifetime, Ali is believed to have retired from public life during the caliphates of Abu Bakr, Umar, and Uthman, which has been interpreted as a silent censure of the first three caliphs. While he reputedly advised Abu Bakr and Umar on government and religious matters, the mutual distrust and hostility of Ali with the two caliphs is well-documented, but largely downplayed or ignored in Sunni sources. Their differences were epitomized during the proceedings of the electoral council in 644 when Ali refused to be bound by the precedence of the first two caliphs. In contrast, Shias tend to view Ali's pledge of allegiance to Abu Bakr as a (coerced) act of political expediency or , thus rejecting that Ali ever pledged. The charge that Ali pledged to Abu Bakr under duress appears also in al-Imama wa al-siyasa, sometimes attributed to Ibn Qutaybah () but possibly written by another Sunni author in the Abbasid era. These conflicts after Muhammad's death are considered as the roots of the current division among Muslims. Those who accepted Abu Bakr's caliphate were later labeled Sunnis, while the supporters of Ali's right to caliphate went on to form the Shia. See also Succession to Muhammad List of Sahabah who did not give bay'ah to Abu Bakr Attack on Fatima's house Notes References Sources Further reading 7th-century Islam History of Islam