Mu'awiya was the founder of the Ummayyad dynasty, and reigned as Caliph from 661-680 A.D..
Mu'awiya was the son of Abu Sufyan, the leader of the Abd Shams clan. Most of the members of this clan rejected Muhammad until the conquest of Mecca in 630. Mu'awiya and his father came to Islam through gifts. Early after his conversion, Mu'awiya worked as one of Muhammad's scribes.
During the reign of the first Caliph Abu Bakr, Mu'awiya fought against the Byzantines in Syria. Caliph 'Umar appointed Mu'awiya Governor of Damascus. 'Uthman gave him control of Syria and north-western Iraq. Mu'awiya had a strong army which he used effectively against the Byzantines.
'Uthman's murder and the accession of 'Ali to the Caliphate in 656 gave Mu'awiya an opportunity to seize power. 'Ali had problems establishing his legitimacy. When 'Ali asked Mu'awiya for an oath of allegience, much of the Syrian population believed that 'Ali was responsible for 'Uthman's murder. Mu'awiya refused to pledge his allegience to 'Ali. The two men fought at the Battle of Siffin in 657 A.D.. Mu'awiya called for arbitration, which ultimately solved nothing. It did, however, delegitimized 'Ali in the eyes of many of his supporters. The Syrians named Mu'awiya the Caliph, and he took Egypt in the same year. Mu'awiya then took over Iraq and moved the seat of the Caliphate to Damascus.
Mu'awiya attacked the Byzantines in Anatolia and in North Africa and conquered Tripolitania and Ifriqiyah, launching attacks into, what is now Algeria. Mu'awiya also led to a three-year seige of Constantinople (674-677) and expanded his empire to the Oxus River.
Mu'awiya governed his empire with a combination of Arab tribal tradition and Byzantine administration. He had the loyalty of the Syrians and pacified the Iraqi tribes by adopting the traditional council of elders where each tribe was represented by its leader at a council that was linked to the caliph through his governors. Mu'awiya also used the Byzantine administrative offices, employing Christians, who in some cases, were from the same families that had served the Byzantine government. Mu'awiya also credited special bureaus, known as diwan, in order to centralize the government.
Mu'awiya's designated his son Yazid as his successor, establishing hereditary succession as the norm for the Caliphate.
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