Geographers historically divided the region into several distinct ethnographic sections based on each area's respective inhabitants.[9]

Commentators in Arabic in the medieval period used the general term bilâd as-sûdân ("Land of the Blacks") for the vast Sudan region (an expression denoting West and Central Africa[10]), or sometimes extending from the coast of West Africa to Western Sudan.[11] Its equivalent in Southeast Africa was Zanj ("Country of the Blacks"), which was situated in the vicinity of the Great Lakes region.[9][11]

The geographers drew an explicit ethnographi