Umar I

Umar I (c. 586-644), second caliph (634-644) of Islam. Next to the prophet Muhammad, Umar was the chief architect of the Islamic state. His conversion, after he had been a bitter opponent of Muhammad, was an important point in the history of Islam. With Abu Bakr, the first Islamic caliph, Umar exercised a decisive influence on Muhammad’s policies. After Abu Bakr died, Umar reigned from 634 to 644.

Like Abu Bakr, Umar maintained that he occupied the caliphal office only as a representative of the one rightful prince, the Prophet Muhammad. Hence, while Abu Bakr called himself khalifah (vicar) of the Apostle of God, Umar initially declared himself khalifah of the khalifah of the Apostle of God. This cumbersome title was later replaced by the shorter forms, khalifah and Commander-of-the-Believers.

Umar, aided by brilliant field generals, conducted military campaigns against the two leading empires of his time, the Sasanians in Persia and the Byzantine Empire in Syria and Egypt. In 644, while the new Islamic state was rapidly expanding, Umar was assassinated by a Persian slave known as Abu-Lu'lu'ah. During the decade of his rule, Umar introduced several regulations that deeply affected the political theory of Islam. He formulated a constitution banning unbelievers from Arabia and awarding the net state revenue to the faithful.