Oyo Empire metropolitan Oyo. This may have been fine in the 15th century when Oyo controlled only its heartland. But to make and maintain farther conquest, the structure underwent several changes. Oyo maintained a semi-standing army of specialist cavalry soldiers called the "Eso", the "Esho" or, formally, the Eso of Ikoyi. These were 70 junior war chiefs who were nominated by the Oyo Mesi and confirmed by the Alaafin of Oyo. The Eso were appointed for their military skill without regard to heritage and were led by the Are-Ona-Kakanfo. After Oyo's return from exile, the post of Are-Ona-Kakanfo was established as the
Oyo, Oyo Oyo, Oyo Oyo is a city in Oyo State, Nigeria, founded as the capital of the Oyo Kingdom in the 1830s and known to its people as 'New Oyo' (Ọyọ Atiba) to distinguish it from the former capital to the north, 'Old Oyo' (Ọyọ-Ile), which had been deserted as a result of rumors of war. Its inhabitants are mostly of the Yoruba people, and its ruler is the imperial majesty Alaafin of Oyo. The major market in the city is Akeesan market, also called Oja Oba (King's market) its very close to the Alaafin's Palace, which is opened on a