In the growing scholarly literature analysing the origins of the territoriality of modern states, the historical roots of territorially homogeneous and exclusive national currencies have been quite neglected. This neglect is surprising not only because these 'territorial currencies' are seen as one of the central symbols of the modem nation-state, but also because it is in the monetary realm where challenges to the practice of territoriality are particularly apparent in the contemporary age. This article analyses the historical reorganization of monetary structures that produced territorial currencies focusing on the North American region. It demonstrates that this development involved a set of elaborate and extensive state initiatives which took place at different speeds after the mid-nineteenth century in Canada, the United States and Mexico. I argue that the different timing of these reforms across the three countries demonstrates well how this monetary transformation was associated closely with the broader political project of building modern nation-states on the North American continent, a process that followed a different trajectory in each country. Specifically, I show that the creation of territorial currencies was seen by state authorities to be intricately connected with the consolidation of three dimensions of nation-states in North America: their economic territoriality, the direct Link created between state and domestic society, and the sense of collective identity among their inhabitants. The analysis contributes to scholarship that historicizes territoriality and the nation-state, as well as to our understanding of the nature and significance of challenges to territorial currencies in the contemporary age. (C) 1999 Elsevier Science Ltd. All rights reserved.