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
History of the world noted for its art, and the Oyo Empire, the Benin Empire of the Edo people centred in Benin City, the Igbo Kingdom of Nri which produced advanced bronze art at Igbo-Ukwu, and the Akan who are noted for their intricate architecture. Central Africa saw the birth of several states, including the Kingdom of Kongo. In what is now modern Southern Africa, native Africans created various kingdoms such as the Kingdom of Mutapa. They flourished through trade with the Swahili people on the East African coast. They built large defensive stone structures without mortar such as Great Zimbabwe, capital of the