Oyo Empire culture in Oyo where victory was obligatory and defeat carried the duty of committing suicide. This do-or-die policy no doubt contributed to the military aggressiveness of Oyo's generals. The Oyo Empire was the only Yoruba state to adopt cavalry; it did so because most of its territory was in the northern savannah. The origin of the cavalry is disputed; however, the Nupe, Borgu and Hausa in neighboring territories also used cavalry and may have had the same historical source. Oyo was able to purchase horses from the north and maintain them in metropolitan Oyo because of partial freedom from the
Yoruba people the monarchy was open to the election of any free-born male citizen. In Ilesa, Ondo, Akure and other Yoruba communities, there were several, but comparatively rare, traditions of female "Ọbas". The kings were traditionally almost always polygamous and often married royal family members from other domains, thereby creating useful alliances with other rulers. Ibadan, a city-state and proto-empire founded in the 18th century by a polyglot group of refugees, soldiers, and itinerant traders from Ọyọ and the other Yoruba sub-groups largely dispensed with the concept of monarchism, preferring to elect both military and civil councils from a pool of eminent