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
Oyo Empire Ajele. These were agents appointed by the Alaafin of Oyo to oversee his interest and monitor commerce. The lead representative of Oyo in the corridor was the Olu, ruler of the town of Ilaro. Ajaland was the last layer added to the empire. It was the most restive and distant, and kept in line with threats of expeditions against it. This territory extended from the non-Yoruba areas west of the Egbado Corridor far into Ewe controlled territory in modern Togo. This area, like all tributary states, was allowed a fair degree of autonomy as along as taxes were paid, the