“…a number of different tribes living in an area between the Ubangi and the Middle Lualaba (Zaire) Rivers. Owing to their close contact with one another, their culture and their stylistic output overlaps. The major tribe in the region is the Ngbaka who inhabit the high plains on the left bank of the Ubangi River. They migrated from the north and settled in their present location – an area controlled by the Ngbandi – in the 1920s. Several political chiefs and family patriarchs rule over the 400,000 people. Ngbaka men farm the land which is their main food resource.”

Source:
Baquart, Jean-Baptiste. The Tribal Arts of Africa. New York: Thames and Hudson Inc. 1998. Print.