East Africa runs from the Ethiopian highlands south through the Rift Valley to the Great Lakes and the Swahili coast, and it holds several religious systems that developed on their own terms.
Waaqeffanna is the indigenous religion of the Oromo, the largest single people of Ethiopia, centred on Waaqa, a sky god understood as the source of a moral order called safuu, approached through ritual specialists and through the seasonal thanksgiving of Irreecha, at which people gather at water to give thanks with fresh grass and flowers. It is bound up with the gada system, an age-grade institution in which men pass through defined stages of eight years and in which political and ritual authority rotates rather than being held for life.
Among the Maasai and related Nilotic pastoralists the religious order is likewise organised through age sets, with initiation, warriorhood and elderhood as ritual stages, and with Enkai as a deity of two aspects, giving and withholding rain. Paul Spencer's study of one Maasai section documents how the ceremonies mediate the friction between generations rather than merely marking their passage.
Along the coast a distinct Swahili Muslim civilisation developed from the ninth century on Indian Ocean trade, with stone towns, Islamic learning in Arabic and Swahili, and a devotional life centred on the mosque, the mawlid and the veneration of teachers.
Sources Oromo Religion: Myths and Rites of the Western Oromo of Ethiopia, an Attempt to UnderstandLambert Bartels with The Maasai of Matapato: A Study of Rituals of RebellionPaul Spencer