A heavily annotated page from a manuscript copy of 'The Decretals of Gregory IX'

The Decretals of Gregory IX (also known as Liber Extra) was created under the authority of Pope Gregory IX (ca. 1145-1241), who ordered Raymond of Penyafort (1175-1275) to edit a cohesive compilation of the collection of papal legislation created by his predecessors.

This would go on to be an authoritative source of Canon Law for the Catholic Church until 1917.

This copy of the Decretals of Gregory IX was created in the thirteenth century and has been heavily annotated by later hands. It was customary to add additional explanations (called a "gloss") in the margins and between the lines.

The main text of this manuscript was written on vellum in the script littera gothica textualis.