Shortly after Oyo Empire expanded her influence westwards, capturing Port Novo and making Dahomey (present-day Benin Republic) a vassal state pay tributes of 40 guns and 400 loads of cowries and corals regularly to Oyo, of course after phases of wars that made Oyo army a dread to the Dahomeyans, Alaafin(Emperor) Labisi appointed a new Bashorun (Prime Minister).
To check the Alaafin from becoming too dictatorial, the Prime Minister according to the constitution could pass a vote of no confidence that would turn the Oyo Mesi
(Legislators) against the Alaafin and an empty calabash would be handed to the emperor signaling that he was required commit suicide and pave way for a new Alaafin since the Oyo Mesi had lost confidence in his rule.
The Basorun was a high priest controlling all the cults except Sango and Ifa, so this could make him declare that the ancestors and Heavens had lost confidence in an
Alaafin. Prior to the appointment of Ga, the unwritten constitution of the empire had been amended from the
more ancient style that the Aremo (heir apparent) ruled after an Alaafin passed on.
The new constitution demanded that the heir apparent died with the Alaafin so as to pass on succession without disputes and in a way make the monarchical system a sort of republic. This made Bashorun Ga more powerful. Ga became despotic and power drunk and from the slightest accusation that an Alaafin or his Prince disrespected the Oyo Mesi to the accusation that an Alaafin was assuming airs of superiority, Bashorun Ga raised five Alaafins to the throne and successively destroyed four of them.
He and his family ruled despotically for twenty years, almost as if they were the Alaafins. By the reign of the fifth emperor, Alaafin Abiodun, the people were fed up of Ga’s dictatorship. On an appointed day, with the support of Aare-Ona Kakanfo(Military Commander of Oyo army) Oyabi, the Alaafin and the people broke the jinx of Ga’s powerful magic and rounded up all his family (except Ojo, Ga’s first son) and were seized and killed, Ga himself was burnt to death in his house.
Abiodun’s reign then went on peacefully and lasted from 1774 to 1789, his was a golden reign. However, the center was no longer holding the seams of the Empire together after 20 years of internal imbalance triggered by Ga. Taking advantage of the lawless years, Egba province under the warrior, Lishabi, had proclaimed their independence and migrated towards their present location in Abeokuta.
The Egbas had been aggrieved by the oppression of the resident Ilaris (governors) in their three provinces within the empire and the absence of any authority to hold them in check. When authority was installed by Abiodun, he sent a punitive expedition against the Egbas, but the rocky hills of Abeokuta made the Oyo cavalry failed woefully in subjecting the Egbas. This triggered a domino effect of provinces declaring their independence from Oyo. Even Dahomey had the effrontery to assault Ketu, a westernmost Yoruba district, without fear of the Oyo imperial army. As far as Ewe (in today’s Togo), Oyo began to wane.
But within the city, Abiodun restated law and order but his reign came to an end with his death in 1789 and a new Alaafin was crowned, Alaafin Awole who reigned between 1789 to 1796). Alaafin Awole did not help matters he could have consolidated Abiodun’s effort to keep the Empire together, but he did not. Under Awole, Afonja was the Aare-Ona Kakanfo (Military Commander), though the two of them had vied for the throne.
It was a taboo in Oyo constitution for the Alaafin and Aare to live in the same city, so while the emperor resided in the capital, the Aare must reside elsewhere, especially a town where enemy threat is imminent. Afonja was also from a royal family but he was slave-born and it was probable this that played against his becoming emperor, though some chiefs of the Oyo Mesi sympathized with him. Afonja’s great-grandfather had been the founder of Ilorin.
Alaafin Awole began to lose the Oyo Mesi’s confidence when he firstly requested Afonja to attack Apomu as part Ofa yearly military exercise the Alaafin must order the Oyo army to revive its strength, but Awole’s omission was that Apomu was an Ile Ife town and it is contrary to the “Coronation Oath” of the Alaafins who all received their Royal swords from Ife and sworn never to raise sword against Ife. Secondly, Awole again ordered Afonja to attack Iwere town, which was a fortified fortress impregnable to Oyo army’s weapons of swords and arrows.