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 in the present Oyo died in 1905. See List of rulers of the Yoruba state of Oyo. During the colonial period, the Yorubas were one of the most urbanized (living in city-like areas) groups in Africa. About 22% of the population lived in large areas with population exceeding 100,000 and over 50% lived in cities made up of 25,000 or more people. The index of urbanization in 1950 was close to that of the United States, excluding Ilorin. The Yoruba continue to be the most urbanized African ethnic group today. Old Oyo linked cities such as Ibadan, Osogbo, and Ogbomoso,