Between 1204 and 1232, Montségur’s castle was reconstructed by Guilhabert de Castres as a strongpoint for the Cathars. By 1232 it – and the village at the base of the pog or rock pinnacle – had become the effective seat of the beleaguered Cathar Church, under the protection of a garrison commanded by Pierre-Roger de Mirepoix, with a population of some five hundred, clergy as well as ordinary believers fleeing Inquisition persecution.
Provoked by de Mirepoix’s raid on Avignonet in May 1242, in which the eleven chief Inquisitors were hacked to pieces, the forces of the Catholic Church and the king of France laid siege to the castle in May 1243. By March 1244, Pierre-Roger, despairing of relief, agreed to terms. At the end of a fortnight’s truce, the 225 Cathar civilians who still refused to recant their beliefs were burnt on a communal pyre on March 16.
Four men who had escaped Montségur unseen on the night of March 15 recovered the Cathar “treasure”, hidden in a cave for safekeeping since late 1243, and vanished. Two of them later reappeared in Lombardy, where these funds were used to support the refugee Cathar community there for another 150 years. More recent New Agey-type speculations, especially in German writings, identify this “treasure” as the Holy Grail, and the Cathars themselves as the Knights of the Round Table.