Nor were the lords of the Languedoc without allies. The King of Aragon, Pedro II, offered his protection to them in 1212, in exchange for them paying homage to him as their overlord. Thinking the King of Spain would be more tolerant of their independent lifestyle – or simply appalled by the atrocities and success of Simon de Montfort – the bulk of the lords of the Languedoc submitted. However, King Pedro proved no match for Simon de Montfort on the battlefield; he was defeated and killed at the Battle of Muret in September 1213. In a second attempt to gain support from a powerful foreign ruler, Raymond VII, the son of Joanna Plantagenet, the sister of Richard I (the Lionheart) and John I of England, forged an alliance in 1241 with his uncle King Henry III, but the army of Louis IX of France defeated the English at Taillebourg a year later.
In short, the bulk of the fighting fell to the intractable people of the Languedoc. Simon de Montfort, the most successful and ruthless of the French invaders, was forced to fight a total of 43 battles or sieges in just 9 years. This was a clear indication of how little he was accepted in the territories given him by the Pope (the Viscountship of Béziers and Carcassonne and the County of Toulouse). He was killed during a second siege of Toulouse in 1218 – allegedly by a stone flung from a mangonel (medieval mechanical stone thrower) manned by women.
His son Amaury tried to continue the war, receiving support from Prince Louis of France (later Louis VIII), but Amaury lacked his father’s military skills or his luck. In 1220, Guy de Montfort, Amaury’s younger brother, was killed in yet another siege, and by 1224, Amaury de Montfort had had enough. He surrendered the lands and titles for which he, his father, and his brothers had fought so bitterly for 15 years and returned to France. For a moment it looked as if the lords of the Languedoc had won.
But the Cathar heresy had not been eradicated, and this provided an excuse for a new crusade. In 1226, Louis VIII took the cross and again brought an army of northern barons and mercenaries into the Languedoc. Within 3 years, the resistance of the southern lords had been broken, and the counts of Toulouse and Foix signed treaties with the French, now led by Louis IX, after his father’s death in 1226.
This time, the Inquisition came with the invaders and established the University of Toulouse to conduct “inquiries” into the Cathar heresy. The systematic methods of the Inquisition made it increasingly difficult for Cathars, particularly the so-called Perfects, the priests (and priestesses) of the Cathars, to survive in the towns and villages of the Languedoc. They retreated more and more to the few strongholds still defended by lords sympathetic to the heresy, notably the mountain fortress of Montsegur. In 1232, the Cathar “Bishop,” Guilhabert de Castres, declared Montsegur the “seat and head” of the Cathar Church. The castle was under the protection of the lords of Pereille and Mirepoix.
The last armed uprising against the French was led by Raymond-Roger de Trencavel, the son of the last Viscount. His father had died in his own dungeon at Carcassonne after surrendering to Simon de Montfort in 1209. In 1240, the younger Trencavel made an attempt to recapture his birthright by force. He was supported by many young men from disinherited families, the so-called faydits. It was some of these desperate men who, on May 28, 1242, murdered 2 inquisitors and some of their servants in Avignonet. It had been the murder of the Papal Legate, Pierre of Castlenau, in 1208 that provoked the first “Albigensian Crusade,” of 1209. The murder of 2 inquisitors in 1242 was the final straw that onvinced the French King it was necessary to destroy the Cathar stronghold of Montsegur.
In 1243, the siege of Montsegur began. By March of the next year, the garrison had suffered a number of casualties, and an outpost had already fallen to the besiegers. The defenders sought and obtained a truce. On March 16, the forces of the King of France took control of Montsegur. 220 men and women, some “Perfects” and some defenders who converted to the Cathar faith now that they could no longer bear arms in its defense, refused to abjure their heresy and were burned at the stake.