1209-1229 AD
The Albigensian Crusade was launched by Pope Innocent III in 1209 against the Cathars (also called Albigensians), a dualist heresy that had gained widespread support in southern France. The Cathars rejected the material world as evil, denied the authority of the Catholic Church, and taught that Jesus was merely a spirit who could not have had a physical body.
The crusade was marked by extraordinary brutality. When the Crusaders captured the city of BΓ©ziers in 1209, they were asked by a messenger which Catholics to spare from the heretics. The legendary response of the cardinal-penalite was: 'Caedite eos. Novit enim Dominus qui sunt eius.' (Kill them all. The Lord will recognize His own.) The entire populationβmen, women, and childrenβwas slaughtered.
The crusade lasted twenty years and effectively destroyed the Cathar movement, but it also devastated the culture and independence of southern France (Occitania), bringing it under the control of the French crown. Key Sources: William of Tudela, La Chanson de la Croisade Albigeoise; Peter of Vaux-de-Cernay, Historia Albigensis; CCC 816-817