Quéribus is sometimes regarded as the last Cathar stronghold. In a sense it was. After the fall of the Château of Montségur in 1244 surviving Cathars gathered together in the Corbières at this mountain-top stronghold on the border of Aragon (The present border between the Aude département and the Pyrénées-Orientales département). The Cathar deacon of the Razès, Benoît de Termes, took refuge here under Chabert de Barbaira, who was finally forced to surrender to Saint-Louis in 1255. The last stronghold to fall, eleven years after the fall of Montségur, Quéribus then became part of the French frontier defence system against Aragon.
This castle is one of the “Five Sons of Carcassonne”, along with Termes, Aguilar, Peyrepertuse and Puilaurens: five castles strategically placed to defend the new French border against the Spanish. It lost all strategic importance after the Treaty of the Pyrenees in 1659 when the border was moved even further south to its present position along the crest of the Pyrenees.