The former Catholic diocese of Narbonne existed from early Christian times until the French Revolution. It was an archdiocese, with its see at Narbonne, from the year 445, and its influence ran over much of south-western France and into Catalonia.
During the French Revolution, under the Civil Constitution of the Clergy, the diocese of Narbonne was combined with the dioceses of Carcassone, Alet, Saint-Papoul and Mirepoix into the new Diocese of the Aude, with its seat at Narbonne. It included 565 parishes. It was a part of the Métropole du Sud, which included ten départements.
The territory of the former diocese of Narbonne was merged under the Concordat of 1801 into the diocese of Carcassonne. After the Restoration of the Bourbons following Napoleon's defeat at Waterloo, an attempt was made to re-establish the see was defeated in the French Parliament (1817).
After nearly a century, a new metropolitan see was created for the Languedoc region, with the elevation of the bishopric of Montpellier to the rank of Metropolitan Archbishop on 8 December 2002. The diocese of Carcassonne was transferred from the metropolitanate of Toulouse to that of Montpellier, and on 14 June 2006 the name of the diocese of Carcassonne was changed to the Diocese of Carcassonne and Narbonne. Toulouse no longer carries the title Toulouse-Narbonne.