Oyo Empire 17th century, Oyo began a long stretch of growth, becoming a major empire. Oyo never encompassed all Yoruba-speaking people, but it was the most populous kingdom in Yoruba history. The key to Yoruba rebuilding of Oyo was a stronger military and a more centralized government. Taking a cue from their Nupe enemies (whom they called "Tapa"), the Yoruba rearmed with armor and cavalry. Oba Ofinran, Alaafin of Oyo, succeeded in regaining Oyo's original territory from the Nupe. A new capital, Oyo-Igboho, was constructed, and the original became known as Old Oyo. The next oba, Eguguojo, conquered nearly all of Yorubaland.
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,