Montségur was the Cathar fortress that fell after a lengthy siege during the Albigensian Crusade. The siege lasted from May 1243 until 16 March 1244, when the stronghold surrendered to French royal and crusader forces. Montségur stood on a steep limestone peak in Occitania, making it both a formidable defensive position and a powerful symbol of Cathar resistance.
The Albigensian Crusade had officially ended with the Treaty of Paris in 1229, but Cathar communities and armed resistance continued in parts of Languedoc. Montségur served as an important refuge and was associated with the Cathar Church. The besiegers faced difficult terrain and determined defenders, eventually capturing a position from which they could attack the fortress more effectively.
After the surrender, Cathar perfecti and other inhabitants who refused to renounce their faith were burned at the foot of the mountain. Modern accounts commonly give the number as about 210 people. Montségur is sometimes confused with Carcassonne or Béziers, both important sites in the same wider crusade, but neither was the fortress that fell in this final, famous siege. The castle visible today is largely a later French border fortification rather than the original Cathar stronghold.