The Cathars presented perhaps the most radical threat to Christian orthodoxy in the Middle Ages, believing that there were two Gods, the God of the spiritual world and the God of the material world in which the soul was imprisoned. To free their souls the Cathars renounced the things of this world, ate a vegan diet, abstained from sexual relations and renounced the Church. This heresy took firm root in the remote, mountainous regions of southern France, and the papacy became increasingly alarmed. Many Cathars came from noble families and senior churchmen in the region had Cathar relatives. In 1208 a vassal of Count Raymond VI of Toulouse murdered the papal legate and Pope Innocent III proclaimed a crusade against the heretics. Raymond soon came to terms with the papal forces, who contented themselves with invading the lands of his vassal Raymond Roger of Trencavel, viscount of Béziers and Carcassone, In July Béziers was sacked and 15,000 townspeople – Cathars and Catholics alike – were massacred. Carcassone surrendered in August. The Trencavel lands were awarded to a northern baron, Simon of Montfort. But Count Raymond’s refusal to assist him in his efforts to eradicate the Cathars gave him a pretext for invasion; in 1211 he tried, but failed, to encircle Toulouse.
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