The Idoma number around half a million people occupying land roughly between the Benue river and the northern fringes of Igboland. This work considers the origins of the Idoma and Idoma ethnicity, various Idoma migrations to the east, west and further south between 1535 and 1805; and the formation of the state in pre-colonial Idomaland. The author also includes some notes on his research methodology - in particular his pioneering efforts to work from oral material; a chronology, and some explanations on the devices used to date early Idoma history. His work is a contribution to an area of Nigerian history which was neglected by the colonial administration and remains under-researched.