The Albigensian Crusade or Cathar Crusade (1209–1229) was a 20-year military campaign. Pope Innocent III started it to eliminate the Cathar heresy in Languedoc and make the Roman Catholic Church supreme there again. The nobles of the Kingdom of France did most of the fighting, and it resulted in a reduction in the number of practicing Cathars. It also resulted in a realignment of Occitania, bringing it into the sphere of the French crown.
|Part of the Crusades|
Massacre against the Albigensians by the Crusaders
County of Provence-Forcalquier
|Commanders and leaders|
|Casualties and losses|
|At least 200,000 to at most 1,000,000 Cathars killed|
|Considered by many historians to be an act of genocide against the Cathars, including the coiner of the word genocide himself Raphael Lemkin|
- Lemkin, Raphael (2012). Jacobs, Steven Leonard (ed.). Lemkin on Genocide. Lanham, Maryland: Rowman & Littlefield. ISBN 978-0-7391-4526-5.
- Pegg, Mark Gregory (2008). A Most Holy War: The Albigensian Crusade and the Battle for Christendom. Oxford, UK: Oxford University Press. ISBN 978-019988371-4.
- Robertson, John M. (1902). A Short History of Christianity. London, UK: Watts & Co.
- Tatz, Colin Martin; Higgins, Winton (2016). The Magnitude of Genocide. ABC-CLIO. ISBN 978-1-4408-3161-4.