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 During the reign of Onigbogi, Oyo suffered military defeats at the hands of the Nupe led by Tsoede. Sometime around 1535, the Nupe occupied Oyo and forced its ruling dynasty to take refuge in the kingdom of Borgu. The Nupe sacked the capital, destroying Oyo as a regional power until the early 17th century. The Yoruba of Oyo went through an interregnum of 80 years as an exiled dynasty after its defeat by the Nupe. They re-established Oyo as more centralized and expansive than ever. The people created a government that established its power over a vast empire. During the