The research includes a study of the global musical repertoire that was created and performed within the context of the cathedrals and collegiate churches in the region of Northern France (county of Artois, French Flanders) during the late Middle Ages and Renaissance. It then examines how and to what extent this repertoire was gradually accepted as the norm for the whole of polyphony in Western Europe during the fifteenth and sixteenth centuries, in order to explain the exceptionally high level, both quantitatively and qualitatively, that music and musical life in the Northern French region were able to reach within a very short space of time.