From the eleventh to the thirteenth century, many archbishops in the western Church turned to the papacy to obtain confirmation of supra-metropolitan prerogatives in harmony with the hierarchical principles of the Gregorian Reform. The study of the proofs produced by these primates makes it possible to identify distinct, contrasting encounters between local ecclesiastical structures and the False Decretals, a canonical collection (c. 836–8/c. 847–52) which was widely disseminated in the central Middle Ages. This process reveals the opposition between two types of territorial primacies, based, on the one hand, on kingdoms searching for unity or, on the other, on the civil provinces of the late Roman Empire.