Historians of migration have increasingly criticized the idea of a ‘mobility transition’, which assumed that pre-modern societies in Europe were geographically fairly immobile, and that people only started to move in unprecedented ways with the onset of modernization in the nineteenth century. In line with this critique, this article attempts to apply thorough quantitative tests to the available data. The focus is on ‘cross-community migration’, following Patrick Manning's argument that migrants moving over a cultural border are most likely to accelerate the rate of innovation. Six forms of migration are considered: emigration out of Europe, immigration from other continents, rural colonization of ‘empty spaces’, movements to large cities, seasonal migration, and the movement of sailors and soldiers. To illustrate regional variations, the examples of the Netherlands and Russia are contrasted. The reconstruction presented here is partial and preliminary, but it unequivocally shows that early modern Europe was much more mobile than modernization scholars allowed for. There was indeed a sharp increase in the level of migration after 1850, but it was due to improvements in transport rather than to modernization in a more general sense. This model has been elaborated for Europe but it can also be applied to other parts of the world and can hopefully contribute to the debate on the ‘Great Divergence’ between Europe and Asia.