was one of the 130 départements of Napoleonic France
, with its capital at Porrentruy
The Mont Terrible for which the département was named is now known as mont Terri, in Jura, Switzerland.
The département was created in 1793 with the annexation of the short-lived Rauracian Republic, created a few months earlier, in the previous year, from a part of the annexed Bishopric of Basel.
In 1797, the old principality of Montbéliard, formerly given to Haute-Saône, was reattached to Mont-Terrible.
The département was abolished in 1800, being annexed to the Haut-Rhin, within which it formed the two arrondissements of Delémont and Porrentruy.
In 1815, the territory that had previously formed part of Mont-Terrible was partitioned between Doubs (Montbéliard) and the Swiss canton of Bern (now forming the canton of Jura and the Bernese Jura).