Albigensian Crusade
The Albigensian Crusade or the Cathar Crusade (1209–1229; , ) was a 20-year military campaign initiated by Pope Innocent III to eliminate Catharism in Languedoc, in southern France. The Crusade was prosecuted primarily by the French crown and promptly took on a political aspect, resulting in not only a significant reduction in the number of practising Cathars, but also a realignment of the County of Toulouse in Languedoc, bringing it into the sphere of the French crown, and diminishing both Languedoc's distinct regional culture and the influence of the counts of Barcelona.