We have seen that slavery, slave trading and pawning were widespread in nineteenth-century Asante society and provided major inputs into the whole range of directly productive activities. This chapter analyses the causes, nature and results of this pattern of interaction between coercion and market forces in the acquisition and use of resources. Besides tackling a crucial aspect of the particular history of Asante social relations of production, this discussion is intended as a case-study in a wide-ranging controversy on which general positions have been strongly stated but which have been remarkably short on systematic empirical investigation. It includes the first attempt to quantify the cost of slave compared to free labour within a precolonial African society. From this analysis I will propose a simple model of the impact of coercion on labour markets in a land-surplus economy.

The classic economic interpretation of slavery, which we may call for generic convenience the ‘Nieboer hypothesis’, explains the existence of widespread slavery as a profit-maximizing response to a scarcity of labour in relation to land, in economies in which capital, however desirable, was not essential for subsistence (as it might be in pastoral societies). The most influential restatements of this tradition, both succinct, were published over a quarter of a century ago. Evsey Domar's 1970 paper was widely discussed by students of serfdom and slavery in Europe and the Americas. For the West African context the Nieboer hypothesis received its classic formulation in five pages by Tony Hopkins in 1973.