She participated in World War II, first on the side of the Allies from 1939 to June 1940, then in the navy of Vichy France until she was scuttled at Toulon in November 1942.

Propelled on the surface by two diesel engines producing a combined 6,000 horsepower (4,474 kW), they had a maximum speed of 18.6 knots (34.4 km/h; 21.4 mph).

Also called "deep-cruising submarines", their range on the surface was 10,000 nautical miles (19,000 km; 12,000 mi) at 10 knots (19 km/h; 12 mph).

[3] From 1930, the French Navy equipped several of its submarines — including Pascal — with hydrophones mounted in front of the forward diving planes and connected to a compesator.

[2] At the start of World War II in September 1939, Pascal was assigned to the 4th Submarine Division in the 1st Squadron, home-ported at Brest.

[2] In November[2] and December[6] 1939, Pascal and Henri Poincaré patrolled in the Atlantic Ocean south of the Azores in search of German U-boats and their supply ships.

[2] At 07:00 on 16 January 1940, Pascal fired a warning shot at a merchant ship her crew suspected of being a blockade runner.

[2][8] As of 1 January 1942, Pascal was assigned to the 5th Submarine Division at Casablanca in French Morocco along with Fresnel, Henri Poincaré, and their sister ship Actéon.

[2] The overhaul took eight months,[2] during which time she was placed under guard in a disarmed and unfueled state in accordance with the terms of the Armistice of 22 June 1940.