There is little that reminds us more of the limitations of thinking according to modern political and ecclesiastical boundaries than the study of the cults of regional saints, a field of research that has been gaining increasing momentum in recent years. This applies right across Europe: one need only think of the borderlands between France, Belgium, the Netherlands, Luxembourg; the shifts in the definition of what is now the Federal Republic of Germany; the State of Bavaria, which once included parts of Austria (and thus the Diocese of Salzburg), or Hungary, which, until after World War I, formed part of the Hapsburg Empire of Austria–Hungary and included Serbia and Transylvania, which continues to have an ethnically mixed population of Hungarian- and German-speakers (as well as Romanian). So also for liturgy and the cults of saints, not least the traces of medieval devotion that are still preserved in liturgical manuscripts held in libraries across modern frontiers and thus belong to a shared history that needs to be included within our purview.