Throughout Western Europe, the dominance of Latin as the language of written culture eroded and local languages became carrieres of politics, religion, culture and science in the early modern and modern periods. This process is sometimes called vernacularization, but it was not a unified process. We aim to describe this process in a more precise way by using library catalogues as data for language use in Europe from the sixteenth century to the early nineteenth century. We further zoom in on different types of cities in different language areas and discuss different publication profiles of university towns, capital cities and commercial centers.