The King of Dahomey was the ruler of Dahomey, an African kingdom in the southern part of present-day Benin, which lasted from 1600 until 1900 when the French Third Republic abolished the political authority of the Kingdom. The rulers served a prominent position in Fon ancestor worship leading the Annual Customs and this important position caused the French to bring back the exiled king of Dahomey for ceremonial purposes in 1910. Since 2000, there have been rival claimants as king and there has so far been no political solution. The Palace and seat of government were in the town of Abomey. Early historiography of the King of Dahomey presented them as absolute rulers who formally owned all property and people of the kingdom. However, recent histories have emphasized that there was significant political contestation limiting the power of the king and that there was a female ruler of Dahomey, Hangbe, who was largely written out of early histories.

Agaja was a king of the Kingdom of Dahomey, in present-day Benin, who ruled from 1718 until 1740. He came to the throne after his brother King Akaba. During his reign, Dahomey expanded significantly and took control of key trade routes for the Atlantic slave trade by conquering Allada (1724) and Whydah (1727). Wars with the powerful Oyo Empire to the east of Dahomey resulted in Agaja accepting tributary status to that empire and providing yearly gifts. After this, Agaja attempted to control the new territory of the kingdom of Dahomey through militarily suppressing revolts and creating administrative and ceremonial systems. Agaja died in 1740 after another war with the Oyo Empire and his son Tegbessou became the new king. Agaja is credited with creating many of the key government structures of Dahomey, including the Yovogan and the Mehu.