Alī ibn Abī ?ālib (Arabic: ??? ?? ??? ????, Transliteration: ?Alī ibn Abī ?ālib, Arabic pronunciation: [??li? ibn ??bi? t????lib]; 13th Rajab, 24 BH – 21st Rama?ān, 40 AH; approximately October 23, 598 or 600 or March 17, 599 – January 27, 661) was the cousin and son-in-law of Islamic prophet Muhammad, ruling over the Islamic Caliphate from 656 to 661. A son of Abu Talib, Ali was also the first male convert to Islam. Sunnis consider Ali the fourth and final of the Rashidun (rightly guided Caliphs), while Shias regard Ali as the first Imam and consider him and his descendants the rightful successors to Muhammad, all of which are members of the Ahl al-Bayt, the household of Muhammad. This disagreement split the Ummah (Muslim community) into the Sunni and Shia branches.