Geography limited precolonial West African export trade to coastal zones.

Evidence

However impressive, this integration of West Africans into the world economy remained very regionalized in 1895, for a variety of ecological, economic, and historical reasons. Among the vast territories conquered by the French, only the Senegambian basin and the coast of Ivory Coast and Dahomey were actively engaged in the commodity export trade. Peanuts and palm kernel required a specific climate and soil. Peanuts did best in light sandy soil and a reliable long dry season. At the same time, as bulky items with a low weight-tovalue ratio, they had to be grown close to the coast, where transportation costs could be controlled. Both of these conditions were met in the Senegambian basin; the Western Sudan, in contrast, although it offered the same soil and climate, was too far from the ocean to make it profitable to grow peanuts for export. — Alice L. Conklin, A Mission to Civilize_ The Republican…, 115