The past decade has seen much ink spilled on global interconnections in the early modern economy, especially those linking European and Asian economies. But this Eurasian concentration has excluded Africa from the discussion. This article addresses this absence by showing that West and West-Central Africa were integral to the global price revolution of the sixteenth and seventeenth centuries. Considering evidence from West and West-Central Africa reveals how the price revolution was a genuinely global phenomenon, with increasing imports of locally-used currencies that created inflation in line with the inflation of gold and silver in Europe and Asia. The article argues that the coexistence of exchangeable value and other social uses of currencies also contributed to a relative depreciation in Africa's global economic strength. Also related to this phenomenon were the rise of an export slave trade and changes in the production and distribution of West and West-Central African cloth industries.

In the seventeenth century, Europeans on the Gold Coast took gold pawns as security for debt, but from the early eighteenth century, they turned increasingly toward the use of human pawns. This shift was the result of a transformation in levels of demand for gold amongst African sellers, most notably the Asante, who began to secure control over local gold sources from c. 1700. The change in demand for gold was accompanied by a rise in slave prices on the West African coast, but it was the indigenous system of debt recovery that proved crucial to the success of European trade.

Studies of slavery in Africa during the period of the Atlantic slave trade have largely ignored questions of how political processes affected enslavement during the period and also the extent to which notions of who could be enslaved were modified. Documentation for the kingdom of Kongo during the 1500s to 1800 allows us to explore how the trade was sustained and the social and political dynamics behind it. In a state that consistently exported large numbers of slaves throughout the period of the trade, kings of Kongo at first observed quite a pronounced distinction between foreign-born captives subject to enslavement and sale in the Atlantic trade and freeborn Kongos who were largely proctected from enslavement and sale overseas. In time, however, the distinctions that separated foreign-born and Kongos fell apart as later political authorities and others disregarded such distinctions and all Kongos became subject to enslavement and sale overseas. This was a product of internal Kongo conflicts, which witnessed the collapse of institutions and the redefinition of polity, what it meant to be a citizen or freeborn, and who could be enslaved.

In Archaeological dialogues 12.2 Jean and John Comaroff explored the role of commensuration – the mechanisms that render equitable and negotiable different orders of value – in the production of society and history. While equilibration, standardization and conversion are implicated in most theories of money and commodification, their nature as social processes has not been adequately specified, above all in the construction of universalizing ideologies and modernist political and economic regimes. They pursue these processes in relation to one African theatre, examining the ways in which different regimes of value, brought up against one another in the encounter between the southern Tswana peoples and European colonizers, became the subject of both conflict and complex mediation. Cows, coin and contracts – which had the capacity to construct and negate difference – soon were invested here with magical qualities. But colonized peoples were also sensitive to the capacity of such currencies to enable or impede convertibility, and to the forms of abstraction and incorporation they permit. Which is why, in South Africa and elsewhere, those currencies often became metonymic of the contestations of value on which colonial struggles, tout court, were played out.

In this short essay they respond to the comments on their article by John Creighton and Laurier Turgeon.

This essay explores the role of commensuration – the mechanisms that render equitable and negotiable different orders of value – in the production of society and history. While equilibration, standardization and conversion are implicated in most theories of money and commodification, their nature as social processes has not been adequately specified, above all in the construction of universalizing ideologies and modernist political and economic regimes. We pursue these processes in relation to one African theatre, examining the ways in which different regimes of value, brought up against one another in the encounter between the southern Tswana peoples and European colonizers, became the subject of both conflict and complex mediation. Cows, coin and contracts – which had the capacity to construct and negate difference – soon were invested here with magical qualities. But colonized peoples were also sensitive to the capacity of such currencies to enable or impede convertibility and the forms of abstraction and incorporation they permit. Which is why, in South Africa and elsewhere, those currencies often became metonymic of the contestations of value on which colonial struggles, tout court, were played out.