About Ali:
Ali ibn Abi Talib was the cousin and son-in-law of the Islamic prophet Muhammad, ruling over the Islamic Caliphate from 656 to 661. A son of Abu Talib, Ali was also the first young male who accepted Islam. Sunnis consider Ali the fourth and final of the Rashidun (rightly guided Caliphs), while Shias regard Ali as the first Imam after Muhammad, and consider him and his descendants the rightful successors to Muhammad, all of whom are members of the Ahl al-Bayt, the household of Muhammad. This disagreement split the Ummah (Muslim community) into the Sunni and Shi`i branches.