History of Africa usually governed by an "oba" and an "iwarefa", a council of chiefs who advised the "oba." by the 18th century, the Yoruba city-states formed a loose confederation, with the "Oni" of Ife as the head and Ife as the capital. As time went on, the individual city-states became more powerful with their "obas" assuming more powerful spiritual positions and diluting the authority of the "Oni" of Ife. Rivalry became intense among the city-states. The Oyo Empire rose in the 16th century. The Oyo state had been conquered in 1550 by the kingdom of Nupe, which was in possession of cavalry,
Oyo Empire preventing the Alaafin from being an autocrat; the Oyo Mesi compelled many Afaafin to commit suicide during the 17th and 18th centuries. The head of the council of Oyo Mesi, the Bashorun, consulted the Ifa oracle for approval from the gods. New alaafins of Oyo were seen as appointed by the gods. They were regarded as "Ekeji Orisa," meaning "companion of the gods." The Bashorun had final say on the nomination of the new Alaafin, his power rivaling the king himself. For example, the Bashorun orchestrated many religious festivals; in addition to being commander-in-chief of the army, which gave him