The structures of organisational power are the subject of this chapter. As a tributary empire, founded upon military conquest, the distinction between ‘conqueror’ and ‘conquered’ was among the most important forms of social differentiation. Membership of the former group implied an elevated social status, often physical separation from the conquered majority in garrisons or on the steppe, and a separate legal status, under the jurisdiction of the command hierarchy of the conquest polity – the Commander of the Faithful (amīr al-mu’minīn) and his sub-commanders (the amīrs). Moreover, the conquerors were the recipients of payments made to them by the conquered. Security and some degree of communal self-governance was the offer in return. The conquered populations retained their own local legal jurisdictions but were governed by the conquerors’ laws where the two groups interacted. Interactions on the empire's frontiers were more violent, unstable and predatory than those in the stable core provinces.

If ‘conqueror’ and ‘conquered’ was a fundamental social distinction, a fundamental social process was its complication over the course of the Umayyad century. In the decades leading up to the crisis of the ‘Abbasid Revolution’ of 747–50, the conquering elite had begun to diversify, with some remaining military specialists, paid from taxation and tribute, and others abandoning military activity for other occupations. The distinction between ‘soldier’ and ‘civilian’ was far from absolute, and individuals could move between activities or combine them. Likewise, from the outset some of the population of conquered lands had found places within the new imperial structures and could undergo processes of religious conversion and cultural or linguistic Arabisation, or both, as they joined, or attempted to join, the new elite. These processes accelerated in the latter part of the Umayyad period in the transition from a monotheist Arabian ‘conquest society’ to more fully articulated ‘Islamic empire’.

These processes had four main phases under Umayyad rule. The first is ‘Uthman's Medinan government of 644–56. ‘Uthman had inherited the structures of the ‘conquest society’. He presided over continued territorial expansion and the transfer of the leading commands and some valuable lands to ‘Abshami allies.