SIMONE IV da MONTFORT. - Leader of the Crusade against the Albigensians. Of a very ancient family, son of Simone III, baron of Montfort, he was born in the second half of the twelfth century and died near Tolosa on 25 June 1218. In 1199 he took the cross for Palestine with Thiebaut di Champagne. On his return to France, he was entrusted with command of the expedition against the Albigensians, which he accepted with great hesitation (1208).
Having assembled a strong army in 1210, he entered the struggle. In 1212 he captured Lavaur after a siege lasting a year, and on 12 September 1213 won the well-known victory of Muret over the united Tolosans and Catalans. The King of Aragon was killed and Count Raimondo of Tolosa fled. Perceiving the knight’s ambition, the Pope proclaimed the end of the Crusade; Simone, however, pursued it with greater ardour than ever. Despite Innocenzo III’s warning, the Lateran Council, which expressly condemned the Albigensian heresy, confirmed S. in possession of the county of Tolosa and the Duchy of Narbona (1215). Yet scarcely a year had passed when he was driven out of Tolosa, which declared in favour of Raimondo. S. proceeded to proclaim the need for a new crusade and undertook the siege of the city, during which he died.