This paper focuses on the development of commercial agriculture in pre-colonial West Africa. The evidence shows that subsistence agriculture was overwhelmingly dominant on the eve of European colonial rule. The historical explanation for this long-delayed development of commercial agriculture in the region is the central analytical task in the paper. Given the initial conditions of a predominantly subsistence agricultural economy, sustained long-run population growth and inter-continental trade are identified as the main drivers of the commercializing process in the long run. The analytical task, therefore, boils down to examining the development of these critical factors over long time periods. We find that both factors grew steadily (with some breaks as would be expected) up to the mid-seventeenth century, when population declined absolutely up to the mid-nineteenth century, at the same time that inter-continental trade in West African commodities also declined. The paper argues that these developments explain satisfactorily the delayed development of commercial agriculture during the period of study. We reject arguments in the literature which attribute the decline of population and inter-continental trade to West Africa’s ecology. We argue instead that the violent procurement of millions of captives shipped across the Atlantic and their employment in large scale production of commodities in the Americas for Atlantic commerce — with the abiding support of mercantilist European states — had profound adverse effects on West Africa’s population and the development of the region’s competitiveness in commodity production for Atlantic commerce.