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 first oba (king) of Oyo, was succeeded by Oba Ajaka, Alaafin of Oyo. Ajaka was deposed, because he lacked Yoruba military virtue and allowed his sub-chiefs too much independence. Leadership was then conferred upon Ajaka's brother, Shango, who was later defined as the deity of thunder and lightning. Ajaka was restored after Sango's death. Ajaka returned to the throne thoroughly more warlike and oppressive. His successor, Kori, managed to conquer the rest of what later historians would refer to as metropolitan Oyo. The heart of metropolitan Oyo was its capital at Oyo-Ile (also known as "Oyo Katunga" or "Old Oyo"