In the districts of Illorin and Borgu, west of the Niger, the inhabitants are also negroes and pagan, but of a more advanced type than the tribes of the river valleys.
The country to the back of Lagos is largely inhabited by Yorubas, and the people of Borgu according to some native traditions claim to have had a Coptic origin.
Illorin and Borgu with a portion of Kabba were already under British rule.
The rulers of other neighbouring provinces offered their allegiance, and by the end of the year 1901 nine provinces, Illorin, Kabba, Middle Niger, Lower Benue, Upper Benue, Nupe, Kontagora, Borgu and Zaria had accepted the British occupation.
For administrative purposes the territories were at first divided into seventeen provinces: Sokoto, Gando, Kano, Katsena, Bornu East, Bornu West, Zaria, Bauchi, Borgu, Kontagora, Nassarawa, Muri, Yola, Bassa, Kabba, Illorin, Nupe.