The Kingdom of Jimma Abba Jifar, established ca 1830, was the largest and most powerful of five monarchies formed by the Oromo peoples in south-western Ethiopia. Based on extensive fieldwork in the area, this work presents a study of the history and organisation of Jimma under its most powerful ruler, Abba Jifar II (1878-1932), stressing the political history and structure of Jimma with a comparative perspective which notes similarities and differences in processes and structures to monarchical systems elsewhere in Africa and the world.