Oyo Empire gunshots scared the Oyo cavalry horses and prevented their charging. Dahomey's army also built fortifications such as trenches, which forced the Oyo army to fight as infantry. The battle lasted four days, but the Yoruba were eventually victorious after reinforcements arrived. Dahomey was forced to pay tribute to Oyo. The Yoruba invaded Dahomey seven times before finally subjugating the small kingdom in 1748. With its cavalry, Oyo campaigned successfully in conquest and suppression over great distances. The Oyo army was able to attack defensive fortifications, but it was harder to supply an army, and they withdrew when supplies ran out.
Oyo Empire despite its violent creation, it was held together by mutual self-interest. The government was able to provide unity for a vast area through a combination of local autonomy and imperial authority. Unlike the great savannah empires, of which Oyo may not be called a successor since it was a successor of Ife, there was little if any Muslim influence in the empire. It is known that at least some Muslim officials were kept in Metropolitan Oyo, and men capable of writing and calculating in Arabic were reported by French traders in 1787. Many believe the decline of the Oyo empire