This period witnessed the establishment of a new regime, its failure to live up to its revolutionary ideals and the gradual dissolution of a vast empire into lesser political entities. The task of creating a political structure supported by viable institutions to rule their territories proved beyond the ''Abbasids. Nor were they able to accomplish the economic integration of the empire, largely because they could not reconcile the economic interests of the rapidly expanding urban centres with those of the rural communities. The result was endemic revolts in rural areas, notably those of Babak, the Zanj and the Qaramita.

The wealth of the ''Abbasid empire attracted vast volumes of international trade. Each region in the empire wished to pursue its own interest in this trade, and competition for an ever-larger share soon developed into uncontrollable interregional strife. Lacking political and economic organization to maintain the integrity of their empire, the ''Abbasids resorted to military power. Consequently military leaders established their own rule in the regions and became powerful adversaries to central government. On the other hand the local populations in the outer provinces rose under their chiefs and also became aggressive opponents. It is these developments that explain the rise of the Tahirids, Samanids, Saffarids, Buyids, Ghaznavids, Tulunids, Hamdanids, and other regional powergroups.

Dr Shaban also studies the rise to power of the Fatimids, who established themselves in power in Tunisia and later in Egypt, replacing the crumbling rule of military dynasties in both provinces. The revolutionary idealism of the Fatimids, however, failed to win the s