M. G. Smith 
Government in Zazzau [PDF ebook] 
1800-1950

Originally published in 1960, this is a details study of the successive forms of government in the Hausa chiefdom of Zaria in Northern Nigeria. It presents a comparative analysis of the political organization and development of Zaria under successive Habe, Fulani and British suzerains. The book tackles the problems of political history and theory from an anthropological point of view, distinguishing governmental forms, functions and modes, as well as elucidating necessary regularities within the processes of political change.