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
Yoruba tribal marks unique to the indigenes of Oyo, Nigeria. The Abaja style of Yoruba tribal mark was inscribed on the cheeks of Lamidi Adeyemi III, the Alaafin of Oyo. The use of tribal marks as a means of identification and beautification among the Yoruba tribe is no longer a norm and some Yoruba states have enacted certain laws that prohibit the use of the marks. Violators of the law are liable to fines or imprisonment (or both). In Oyo State, for example, the prohibition of tribal marks is an integral part of the state Child Rights Law, a law that imposes a