A group of 'Ali's followers. Mu'awiya (the Muslim Governor of Damascus) attempted to take the Caliphate from 'Ali (Muhammad's son-in-law and the 4th "orthodox" Caliph). This started the first civil war in Islam. 'Ali won the Battle of Siffin (657 A.D.) but eventually lost when he was compelled, by Mu'awiyah, to submit his claim to the Caliphate to arbitration. The Kharijites were mostly desert Arabs who loved the democratic free spirit of their environment. They objected to 'Ali's compromise and his submission to arbitration and they broke away from him, insisting that there should have been no appeal "save to the Book of Allah".
These men, known later as Khawarij (Kharijites), went even further, and insisting that the Caliph should be elected by all Muslims, not just the Quraysh tribe. The Kharijites fought against other Muslims and refused to associate with those who did not share their religious and political beliefs. They even killed the children of unbelievers. A moderate faction of the Khawarij known as Ibadis (named after the leader 'Abdullah ibn-Ibad), exists today in Algeria, East Africa, and Oman. (Source: Caesar E. Farah, Islam: beliefs and observances, Woodbury, N.Y., Barron's Educational Series [1970], p.175.)
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