The Hadiyya are an ethnic group of 1.5 million people in central-southern Ethiopia. Linguistically they belong to the Highland East Cushitic cluster. In Ethiopian and Arabic chronicles between the 13th and the 17th centuries they were mentioned as representatives of a powerful Muslim state which continuously challenged the hegemony of the Christian Ethiopian Empire in that region. Following the expansion of the Oromo from the 16th century onwards the Hadiyya were territorially fragmented and adopted different ethnic identities, for example, of Gurage, Allaaba, Sidama and Oromo. In their historical traditions they however preserved the memory of a common origin, the Hadiyya state. As this becomes most evident among the people who have maintained the ethnonym Hadiyya to this day, Ulrich Braukämper focused his study of the Hadiyya in this area. Because it was taking place in an illiterate culture, the reconstruction of history until the conquest of the area by the Ethiopian Empire in the second half of the 19th century had to be based on oral traditions. The results of this event were deep-rooted, whereas the brief phase of Italian colonialism (1936-41) remained peripheral. Braukämper's chronological representation ends with the Ethiopian Revolution of 1974, and it is presently complemented by an ethnographic monograph of the Hadiyya proper. The revised and translated edition of the book published in 1980 was done on the explicit request of members of the Hadiyya people.