This corresponds to an eventful period for the abbey during which its privileges were contested by the Dukes of Normandy.

The cartulary would have served to justify these privileges granted by the Pope, the King of France and the former dukes.

These are the last remaining charters of the Mont-Saint-Michel Abbey, those preserved in Saint-Lô having mostly been destroyed by fire during the bombardment of the city in 1944.

The initials of the oldest part are black in colour, and contain fantastic animals mixed with interlacing: unicorns, billy goats, owls and werewolves, inspired by Physiologus or by folklore.

[5] The manuscript also contains four miniatures covering all or most of their page:[6] The style of these miniatures is not inspired by the Norman Romanesque illumination of this period, but is similar to that of illuminations made on the banks of the Loire or in the region of Le Mans, certain details being reminiscent of the stained glass windows of Le Mans Cathedral.