Pseudo-Isidorian Decretals

Pseudo-Isidore is the conventional name for the unknown Carolingian-era author (or authors) behind an extensive corpus of influential forgeries. Pseudo-Isidore's main object was to provide accused bishops with an array of legal protections amounting to de facto immunity from trial and conviction; to secure episcopal autonomy within the diocese; and to defend the integrity of church property. The forgeries accomplished this goal, in part, by aiming to expand the legal jurisdiction of the Bishop of Rome.

Pseudo-Isidore used a variety of pseudonyms, but similar working methods, a related source basis, and a common vision unite all of his products. The most successful Pseudo-Isidorian forgery, known as the False Decretals, describes itself as having been assembled by a certain Isidorus Mercator (in English: Isidore the Merchant). It is a vast legal collection that contains many authentic pieces, but also more than 90 forged papal decretals. Pseudo-Isidore also produced a compendium of forged secular legislation pretending to be the laws of Charlemagne and Louis the Pious, under the pseudonym Benedictus Levita (Benedict the Deacon). Almost everything about Pseudo-Isidore's identity is controversial, but today most people agree that he worked in the archiepiscopal province of Reims in the decades before 850; and that he conducted important research at the library of the monastery of Corbie.