The Albigensian Crusade was launched in 1209 against Cathars and their protectors in southern France. Northern French crusaders, local lords, church authorities, and the counts of Toulouse became involved in a brutal conflict. The campaign combined religious repression with territorial conquest and political centralisation.
The crusade matters because it shows crusading turned inward within western Christendom. It devastated parts of Languedoc and strengthened northern French and royal influence over the south. It also left a long memory of religious persecution, cultural loss, and regional resistance.
Kate Mosse’s Labyrinth and wider Languedoc fiction are strongly connected to Cathar memory and the Albigensian Crusade. The setting suits novels about hidden faith, besieged towns, family secrets, inquisitors, troubadour culture, and the collision between local identity and crusading violence.