The “Tresor des Chartes” is the most valuable and iconic archive of the French kings and has been built as a collection as early as in the 13th c. Within the “Tresor”, the collection of medieval registers (aka “Chancery corpus”) stand out. They keep record of the charters, grants and privileges given by the king of France and were produced directly by the French royal chancery. Dating from 1302 to 1483, they contain ca. 68,000 charters and documents. This large and iconic collection bears witness to the rationalization of late medieval administration and is a key source to our understanding of medieval Europe and the rise of centralized nation state on the continent as a consequence of the long lasting wars between France and England.