Dahomey conquered Allada, the origin for the royal family according to oral tradition, and in 1727 he conquered Whydah. This increased size of the kingdom, particularly along the Atlantic coast, and increased power made Dahomey into a regional power. The result was near constant warfare with the main regional state, the Oyo Empire, from 1728 until 1740. The warfare with the Oyo empire resulted in Dahomey assuming a tributary status to the Oyo empire. Tegbesu, also spelled as Tegbessou, was King of Dahomey, in present-day Benin, from 1740 until 1774. Tegbesu was not the oldest son of King Agaja (1718–1740), but
Dahomey was selected following his father's death after winning a succession struggle with a brother. King Agaja had significantly expanded the Kingdom of Dahomey during his reign, notably conquering Whydah in 1727. This increased the size of the kingdom and increased both domestic dissent and regional opposition. Tegbessou ruled over Dahomey at a point where it needed to increase its legitimacy over those who it had recently conquered. As a result, Tegbesu is often credited with a number of administrative changes in the kingdom in order to establish the legitimacy of the kingdom. The slave trade increased significantly during Tegbessou's reign