In France the Cathars grew to represent a popular mass movement and the belief was spreading to other areas. The Cathar Crusade was initiated by the Roman Catholic Church to eliminate the Cathar heresy in Languedoc. Heresy was a major justification for the Inquisition (Inquisitio Haereticae Pravitatis, Inquiry on Heretical Perversity) and for the European wars of religion associated with the Protestant Reformation.
What was a major reason and justification for the Europian wars of religion?
Heresy