The Rashidun Caliphate
Also called: Rightly Guided Caliphs
After Muhammad’s death four caliphs, from Abu Bakr to Ali, led the Muslim world. In this period the Arabs conquered Byzantine Syria and Egypt and Sasanian Persia.

In the Sunni account Muhammad died without naming a successor, and the elders of the community chose his companion Abu Bakr as “successor of the Messenger of God” — the caliph (Shia Muslims hold that Muhammad had designated his son-in-law Ali). Umar, Uthman and Ali followed in turn, and the rule of these four (632–661) is called the Rashidun, or “rightly guided”, caliphate, with its capital at Medina. Abu Bakr brought back the tribes that had broken away after Muhammad’s death (the Ridda wars), and under Umar the Arab armies struck two empires exhausted by long war, taking Syria, Jerusalem and Egypt from Byzantium and Iraq and the Iranian plateau from the Sasanians.
Conquered peoples were not forced to convert. Jews, Christians and others could keep their faith by paying a poll tax (jizya) and a land tax (kharaj); the saying “the sword in one hand and the Qur’an in the other” does not fit the facts. Arab warriors lived on salaries in garrison cities such as Kufa, Basra and Fustat, and Umar fixed the Islamic calendar from the year of the Hijra.
Yet quarrels over succession grew. When Uthman was murdered by rebels in 656, Ali became caliph, but Uthman’s kinsman Muawiya, governor of Syria, refused to accept him and civil war followed. With Ali’s assassination at Kufa in 661 and Muawiya’s founding of the Umayyad dynasty, the age of elected caliphs came to an end.