The story of the revolt of the Zanj slaves in southern Iraq has always been seen as a striking exception among the political and social movements of the Abbasid period. Rather than being based on religious differences and struggles for authority in the Muslim community, it seems to be based on secular concerns and class warfare. The basic facts are well-known and not really in dispute whilst the military conflict is covered in minute and sometimes wearisome details. The Zanj were able to dominate much of southern Iraq for almost a quarter of a century from 869 to 883. But beyond this apparent clarity, lie some interesting and revealing ambiguities and differences of interpretation.
Zanj was the name given to the slave population of southern Iraq, most of them of East African origin. Since early Islamic times, large numbers of slaves had been used by landowners in the marshes and deserts of southern Iraq, the breadbasket of the early caliphate, to reclaim land by irrigation. Under Islamic law, reclaimed land brought under cultivation belonged to the man who made it productive and so it was worth investing large sums in this work. Not only that, but there were tax breaks too: such reclaimed land paid much less than the state demanded from already cultivated areas. The rich and entrepreneurial members of the early Muslim elite saw these opportunities and rushed to exploit them. As in the ante-bellum American south, there was not enough local labour and work was too unpleasant (hard digging in a shadeless landscape in temperatures which regularly topped 40 degrees) to be able to entice free men from other areas of the Muslim world. As time went on the work became even harder as they were forced to dig off the large quantities of salt which accumulated on the land, backbreaking and extremely unpleasant work. This salinisation threatened the whole productivity of these valuable estates. We have no knowledge of who the slave traders were or where exactly their victims came from but we can be fairly sure that the traders were Gulfi merchants and the Zanj came from the East African littoral.