Most peoples of the period of the seventh to eleventh centuries followed one or the other of two major religious systems.
Across much of the Kenya interior and south through central Tanzania there prevailed the belief in a single Divinity, usually identified metaphorically with the sky. The existence of evil was understood in this religion to derive usually from divine retribution or judgment. Ancestor spirits were not significant objects of religious concern. Versions of the religion among Cushitic-speaking peoples sometimes added a belief in lesser spirits capable of harm, and some of the rift Southern Cushites had developed a different celestial metaphor, linking Divinity to the sun rather than to the sky in general. This latter variety of the religion had been adopted some centuries before the turn of the era by the Southern Nilotic ancestors of the Tato and the Kalenjin.
In much of the southern half of the East African interior and through much of the Great Lakes region, a different religion prevailed. Brought in by Bantu settlers at the start of the Early Iron Age, this set of beliefs recognized the existence of a creator God , but its primary religious observances were directed toward the ancestors. Evil was attributed most often to human malice and envy: to the work of persons called, in European translations of the African names for them, ‘witches’ or ‘sorcerers’. In the Lakes region there eventually arose an additional stratum of spirit belief. Spirits of higher status and farther-reaching influence than one’s ancestors are now widely turned to by supplicants in that region. This level of religious practice may go back to proto-Lacustrine times at the turn of the era, but
it seems probable that it began to take on pre-eminent importance only during the second millennium, as the religious counterpart of, and often reaction to, the growth of political scale in later eras.
In the central East African interior where both religions were practised, the trend of the past two thousand years has been toward blending the elements of the two philosophies. A couple of significant manifestations of this trend belong to the period from the seventh to the eleventh centuries. In western Kenya the idea of the ancestors as an important focus of religious observance diffused, presumably from the pre-Luyia-Gisu, eastward to the pre-Kalenjin during that era, and the concept of witchcraft had apparently become part of the Kalenjin explanation of evil by the end of the first millennium also. In North Pare and adjoining areas of Kilimanjaro, the God-sun metaphor took hold in proto-Chaga religious thought at around the beginning of the second millennium. The proto-Chaga incorporation of Old Asa people apparently added Southern Cushitic concepts of Divinity onto a still active concern for the ancestors, derived from the Bantu portion of the Chaga heritage, just as the contemporaneous assimilation of Old Ongamo people brought about a major modification of age organization in the society. But elsewhere the era does not seem to have been marked by great change in values or beliefs.
C. Ehret (U.S.A.); linguist and historian of East Africa; has published many works and articles on the pre-colonial and colonial history of East Africa. Faculty at the University of California, Los Angeles.
Source: General History of Africa Vol.III. [Editor: M. El Fasi, Assistant Editor: I. Hrbek] Africa from the Seventh to the Eleventh Century. Chapter 22. The East African Interior