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
Nupe people Nupe people The Nupe, traditionally called the Tapa by the neighbouring Yoruba, are an ethnic group located primarily in the Middle Belt and northern Nigeria, and are the dominant group in Niger State, an important minority in Kwara State and present in Kogi State as well. The Nupe trace their origin to Tsoede who fled the court of Idah and established a loose confederation of towns along the Niger in the 15th century. The proximity of Nupe to the Yoruba Igbomina people in the south and to the Yoruba Oyo people in the southwest led to cross-fertilization of cultural influences