Umayyad rule was divided between two branches of the family: the Sufyānids (reigned 661–684), descendants of Abū Sufyān; and the Marwanids (reigned 684–750), Marwān I ibn al-Hakam and his successors. The Sufyānids, notably Muʿāwiyah I (reigned 661–680), centralized caliphal authority in Damascus. The Syrian army became the basis of Umayyad strength, enabling the creation of a united empire through greater control of the conquered provinces and of Arab tribal rivalries. Muslim rule expanded to Khorāsān, garrison cities were founded at Merv and Sīstān as bases for expeditions into Central Asia and northwestern India, and the invasion of northwestern Africa was begun. A new fleet conducted a series of campaigns against Constantinople (now Istanbul; 669–678), which, while ultimately unsuccessful, offset the secular image of the state because they were directed against the Christians. Though the Sufyānids generally retained the Byzantine and Persian administrative bureaucracies they inherited in the provinces, they were politically organized along Arab tribal lines, in which the caliph was chosen by his peers to become, theoretically, “first among equals” and act on the advice of a shūrā (tribal council). Muʿāwiyah, however, in securing during his lifetime an oath of allegiance to his son Yazīd I, disregarded the traditional election (bayʿah) and introduced the alien concept of hereditary succession. Civil war and the deaths of Yazīd I in 683 and Muʿāwiyah II in 684 brought Sufyānid rule to an end. Marwān I was proclaimed caliph in Syria in 684 amid tribal wars (Source: Britanica).
Ummayyads in Persia: Abdul Malik I and His Economic Initiatives
