Wassoulou is a cultural area and historical region in the Wassoulou River Valley of West Africa. It is home to about 160,000 people, and is also the native land of the Wassoulou genre of music.
Wassoulou surrounds the point where the borders of three present-day countries meet: Mali, Côte d'Ivoire, and Guinea. It includes portions of southwestern Mali, northwestern Côte d'Ivoire, and eastern Guinea. It is bordered by the Niger River to the northwest, and by the Sankarani River to the east.
The name Wassoulou is alternately spelled Wassulu, Wassalou, and Ouassalou.
Wassoulou is best known internationally as the birthplace of Wassoulou music, a style which blends traditional and modern influences with strong female vocalists and a pentatonic hunter's harp. Wassoulou music is one of the two forms of West African music ethnomusicologists believe to be the origin of the American blues, which developed out of music forms dating back to the American slave trade from West Africa. Some of the most famous residents of Wassoulou include the singers Oumou Sangare, Ramata Diakite and Coumba Sidibe.
Wassoulou's cultural importance is reflected in the development of internet resources, and the creation of Radio Wassoulou broadcasting from Yanfolila.
Wassoulou is also a dialect of the Eastern Maninkakan language, and is closely related to Kankan Mandinka. Speakers of Wassoulou number some 73,500 in Guinea, with 41,200 speakers estimated in Mali, where the closely related Bamanankan is also spoken. In the far northwest of Côte d'Ivoire there are some 21,000 Wassoulou speakers, where it is related to Wojenaka Maninka.
Inhabitants are known as Wassulu, Wassulunka or Wassulunke.
The Wassoulou area is a center for the mingling of several ethnic groups. The nomadic Fula people, who were believed to have emigrated from the Fouta Djallon highlands to the west, integrated into the indigenous Mandé people and adopting their language and customs sometime prior to the 18th century, at roughly the same time Islam spread into the area. There are also large populations of Malinke peoples native to Wassoulou.