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 moved further south, to Ago d'Oyo. Oba Atiba sought to preserve what remained of Oyo by placing on Ibadan the duty of protecting the capital from the Ilorin in the north and northeast. He also attempted to get the Ijaye to protect Oyo from the west against the Dahomeans. The center of Yoruba power moved further south to Ibadan, a Yoruba war camp settled by Oyo commanders in 1830. Atiba's gambit failed, and Oyo never regained its prominence in the region. Oba Atiba otherwise called Atiba Atobatele died in 1859; His son Adeyemi I and the 3rd Alaafin to rule