Anthropologists and historians of eastern African societies have long shared a common interest in the description and analysis of African religions and beliefs. Spirit possession, mediumship, witchcraft beliefs, diviners and divinatory techniques, the role of prophets and the nature of prophetic traditions are all subjects for which there is now an extensive, and still growing, body of literature. For virtually no group of the present ethnographic map of eastern Africa do these topics remain unstudied. Yet the sheer diversity of the material has contributed to a degree of confusion i n the analytical categories and labels that have been employed in describing such religious phenomena.