Fanjeaux constitutes a significant crossroads of transportation communication channels to the borders of Razès and Lauragais. Also, the Romans had been installed on this point, setting up there a temple dedicated to Jupiter, the origin of the name of the commune: Fanum Jovis A their turn, the feudal ones had raised a significant fortified town there. More than 50 noble families had their residences in the castrum of Fanjeaux. Two coseigneurs dominated however: Ram Na Cavaers and Guillaume de Durfort. As of XIIème century, the nobility of Fanjeaux was won over to the catharism. Male and female heretic communities were even established in the locality, the textile activities (workshops of weaving, dyeings...) there were particularly active, supporting the proselytism of the Good Men, Since 1193, the bishop cathare Guilabert de Castres had been established there. The village then constituted a bastion of Albigéisme, very attended by the cathares of the area.
In 1206, a team of legates cistercians, accompanied by the bishop of Osma and Domenica de Guzman, took the road of Lauragais in order to évangéliser the region. As of this date, Domenica fixed at Prouilhe the seat of his first community which will become the command of Dominican into 1215. He remained several times at Fanjeaux (of 1206 towards 1216) where he was named cleaned into 1214. In same time, in 1209, the head of cross the Simon de Montfort, invests the village.
After the passage of Domenica and under the impulse of the brotherhoods, in particular that of Our-Lady whose statutes go up to 1266, Fanjeaux redoubled its spiritual activity.
Placed on the way of the incursion of the English, the locality concealed burned by the armies of Prince Noir into 1355 then quickly rebuilt. Thereafter, in XVIème century, the village knew a new prosperity thanks to the culture of the pastel.
During the revolutionary period, one entant of Fanjeaux was distinguished particularly. Politician faithful to his republican convictions, Hugues Destrem, after having been a mayor of his native village in 1783, was elected appointed with the Legislative Assembly (1791-1792). Representing with the Council of the Five Hundreds in 1798, it disapproved Bonaparte at the time of the coup d'etat of the 18 brumaire. This opposition was worth the banishment to him.
Equipped with 2092 inhabitants in 1790, then 1307en 1891, the common one counts 855 Fanjuvéens in 1990. Currently chief town of the canton, Fanjeaux is primarily turned towards the agricultural activity and the tourist greeting. It is one of the saint-Dominican top-places.