The Kigdom of Baol in central Senegal was one of the kingdoms that arose from the split-up of the Empire of Jolof (Diolof) in about 1549. It included a strip of land extending east from the ocean (from old Portudal on the coast south of Cap-Vert, where Dakar is) inland to Diourbel and including Touba and MBacke. It was directly south of the Kingdom of Cayor and north of the Kingdom of Sine.

The "Tiegne" or king of Baol was a relative of the "Damel" (king) of Cayor. The kingdom was founded in secession from the third Damel of Cayor, by his own son, who killed him, and the history of Baol includes repeated attempts, only sometimes successful, of the Damels of Cayor to re-conquer Baol. At one time the Serer king of the Kingdom of Sine also was the Tiegne of Baol. Baol and Cayor were reunited under the 14th Damel near the end of the 18th century.

Cayor and Baol were conquered by the French in the 19th century along with the rest of Senegal, in the campaigns of Governor Louis Faidherbe.

Cayor was ethnically a Wolof kingdom, but it included communities of Serer-Safen and other Serer groups. The social and political systems were basically the same as those of Cayor.