This chapter discusses the events around Mainz and popular image of medieval repression. Indiscriminate persecution was to be replaced by the methodical application of law. Protestant historians, from the sixteenth century onward, sought roots for their reforms in the heresies of earlier periods, and hence associated their contemporary struggles with past persecution, depicting an all-powerful and highly repressive Catholic Church. Elements of this viewpoint continued to inform the foundational histories of medieval repression written in the late nineteenth and twentieth centuries. At the Third Lateran Council various named heretical groups were anathematised, using measures designed to enlist the aid of local secular powers against them. The Franciscan preacher Bernard Delicieux famously led a popular and legal revolt against inquisition in southern France. In various ways, the mechanisms of repression were prey to the vicissitudes of local politics and attitudes.