History of the Yoruba people military capital of Ilorin, and then sacked and destroyed Ọyọ-Ile, the royal seat of the Ọyọ Empire. Following this, Ọyọ-Ile was abandoned, and the Ọyọ retreated south to the present city of Oyo (formerly known as "Ago d'Oyo", or "Oyo Atiba") in a forested region where the cavalry of the Sokoto Caliphate was less effective. Further attempts by the Sokoto Caliphate to expand southwards were checked by the Yoruba who had rallied in defence under the military leadership of the ascendant Ibadan clan, which rose from the old Oyo Empire, and of the Ijebu city-states. However, the Oyo hegemony had
Oyo Empire layer of the empire was composed of the towns closest to Oyo-Ile, which were recognized as brothers. This area was south of metropolitan Oyo, and its Yoruba inhabitants spoke different dialects from that of Oyo. These tributary states were led by their own rulers, titled Obas, who were confirmed by the Alaafin of Oyo. The empire's third layer was the Egbado Corridor southwest of Yorubaland. This area was inhabited by the Egba and Egbado, and guaranteed Oyo's trade with the coast. The Egba and Egbado tributaries were allowed, like their Yoruba counterparts, to rule themselves. They were, however, supervised by