In a series of studies about settlement density in the Rhine area from protohistoric to modern times, K.-P. Wendt and A. Zimmermann try their hand at the difficult task of evaluating the palaeodemography of a region. Their task is all the more complex because these are times and spaces for which written sources are lacking, as a result of which reasoning relies very broadly on interpretation of the archaeological record. The two researchers also attempt to characterize the density of rural settlements and their spatial distribution. I shall not dally on the methods employed, which involve quite complex statistics and geomatics (anyway, they lie outside my area of scientific competence), and shall take the figures at face value, even if I might question some of them. I shall contemplate the economic impact of population growth on the countryside of Gaul in Imperial times. It is a subject that has often been addressed, but one which I intend to reconsider in the context of a European programme on this issue. The relationship between population numbers, agricultural yield, gross domestic product and taxation has certainly been one key to our understanding of the Roman economy ever since the model suggested by K. Hopkins. Here, however, I do not wish to proceed in terms of theory, but intend to review critically the archaeological sources, which, for want of written evidence, are our mainspring for evaluating the key components of economic development on the regional scale of NE Gaul.