History / The Albigensian Crusade or Cathar Crusade (1209-1229)The Crusaders in front of B閦iers; July 22; 1209.(After the assassination of Pierre de Castelnau on January 14; 1208; Pope Innocent III decided to launch a crusade against the Cathars. Crusaders decided to attack the viscount of B閦iers with a 20;000 men army. Arnaud Amaury; a pontifical legate and abbot of C顃eaux; reportedly declared: "Kill them all; God will acknowledge his own"; and the city was taken by surprise; sacked and its inhabitants massacred).Engraving (1862); Private collection.