Pope Innocent III and the Annulment of Magna Carta

Abstract

Historians have offered a variety of explanations for Pope Innocent III's release of King John from the promise that he made to observe the clauses of Magna Carta. None has won general acceptance. This article proposes an alternative by examining the tenets of the canon law as it was understood in 1215. That examination shows that the law of oaths (De iureiurando) played a central role in canonistic thought of the time. It contained the juristic resources that made it possible for Innocent to release John from the oath that he had taken at Runnymeade.