Lagarde (French pronunciation: [laɡaʁd]; Occitan: La Garda) is a commune in the Ariège department in southwestern France.

The Château de Lagarde is an imposing medieval building constructed in the 11th century with the first square tower (1063–1065) by Ramiro I, King of Aragon and Count of Barcelona.

Between the 1176 and 1180 the chateau developed with 4 square towers and with a rectangular entry with a door made out of wood, a drawbridge and ditch at the foot of the walls.

Simon de Montfort, 5th Earl of Leicester allotted the village of Lagarde and its castle to Guy I of Lévis, lieutenant of his army, in 1212.

This was conducted after Simon de Montfort convened at Pamiers in a general meeting of nobles, prelates and noted middle-class men, where they drew up a 46 article administration doctrine of the place.