 To the east of the Abomey plateau, the Oyo Empire (in present-day Nigeria) was at the peak of its power and exercised some hegemony over the tribes in the area.To the south, there were two prominent kingdoms, Allada and the Whydah, which had power along the Atlantic coast.The coastal area had come in contact with the Portuguese in the 15th century, but significant trade did not start until 1533 when the Portuguese and the city of Grand-Popo signed a trade agreement.