From the First Fitna until his disappearance from the historical record in the 660s, Abu al-A'war served Mu'awiya in a number of capacities, including as a commander and negotiator at the Battle of Siffin, an operative of Amr ibn al-As in Egypt, a tax administrator in Palestine and the governor of Jordan; he had held the latter post since the reign of Uthman.
His father was Sufyan ibn Abd Shams, a chieftain of the prominent Dhakwan clan of the Banu Sulaym, a nomadic Arab tribe that dominated the Harra region in the north-central Hejaz (in present-day western Saudi Arabia) and had strong links to Medina and Mecca.
[7] According to Michael the Syrian, shortly after this, in 653/654, Abu al-A'war commanded an expedition against Kos, which was captured and plundered due to the treason of the local bishop.
[8][dubious – discuss] Finally in 654 he commanded the Arab fleet in the great Battle of the Masts, where the Byzantine navy under Emperor Constans II was annihilated.
[9][7] According to Armenian and Byzantine sources, his fleet continued onward to besiege Constantinople but a storm destroyed the ships carrying siege engines.
Caliph Uthman (r. 644–656), who belonged to the Umayyad clan, appointed Abu al-A'war as governor of Jund al-Urdunn (military district of Jordan) with its capital in Tiberias.
[2] Following the fighting at Siffin, Abu al-A'war was one Mu'awiya's representatives in the settlement negotiations with Ali, and he prepared the preliminary draft for the caliphal succession conference in Adhruh, a town in the Sharat highlands.
[2][5] After Mu'awiya succeeded Ali in 661 and established the Umayyad Caliphate, he intended to replace Amr, his independent-minded governor in Egypt, with Abu al-A'war, but this plan never came to fruition.