History of Nigeria city-states. A state council (the "Oyo Mesi") named the "Alaafin" (king) and acted as a check on his authority. Their capital city was situated about 100 km north of present-day Oyo. Unlike the forest-bound Yoruba kingdoms, Oyo was in the savanna and drew its military strength from its cavalry forces, which established hegemony over the adjacent Nupe and the Borgu kingdoms and thereby developed trade routes farther to the north. The Benin Empire (1440–1897; called "Bini" by locals) was a pre-colonial African state in what is now modern Nigeria. It should not be confused with the modern-day country called Benin,
Oyo Empire The Oyo did not use guns in its major conquests. The military waited until the 19th century to adopt them. In 1764, a joint Akan (Akyem)-Dahomey-Oyo force defeated an Asante army. The alliance victory defined borders between the neighboring states. Oyo led a successful campaign into Mahi territory north of Dahomey in the late 18th century. The Yoruba also used the forces of their tributaries; for instance, they accomplished a 1784 naval blockade of Badagri with an Oyo-Dahomey-Lagos force. At the beginning, the people were concentrated in metropolitan Oyo. With imperial expansion, Oyo reorganized to better manage its vast holdings