Montclair castle was built by Arnulf von Walecourt in the late 12th century. The site was a fief from Trier archbishop. The castle was built to the site of old Frankish castle. In 1351 the castle was conquered and razed by the troops of Archbishop Baldwin of Luxembourg. Jakob von Sierck built the new castle in 1434-1439. It fell into disrepair and started to decay in the 17th century. Montclair was restored in 1992-1993.
References:The Château de Foix dominates the town of Foix. An important tourist site, it is known as a centre of the Cathars. Built on an older 7th-century fortification, the castle is known from 987. In 1002, it was mentioned in the will of Roger I, Count of Carcassonne, who bequeathed the fortress to his youngest child, Bernard. In effect, the family ruling over the region were installed here which allowed them to control access to the upper Ariège valley and to keep surveillance from this strategic point over the lower land, protected behind impregnable walls.
In 1034, the castle became capital of the County of Foix and played a decisive role in medieval military history. During the two following centuries, the castle was home to Counts with shining personalities who became the soul of the Occitan resistance during the crusade against the Albigensians.