During World War II, she operated on the Allied side until 1940, when she became part of the naval forces of Vichy France.

[3] Sybille was authorized in the 1929 naval program,[1] and her keel was laid down at Chantiers Worms le Trait in Rouen, France, on 10 January 1931.

In 1940 the Allies made plans to intervene in Norway to prevent the shipment of iron ore from Sweden to Germany via Narvik on the Norwegian coast.

Allied operations related to Norway became of greater urgency when the German invasion of both countries began on 9 April 1940.

As they supported Allied operations in the Norwegian campaign, the French submarines found limited facilities available to them at Harwich and had to rely largely on Jules Verne and spare parts sent from Cherbourg in France for repairs, some of which never were completed.

[1] By 6 May 1940 the Allies had indications that a German invasion of the Netherlands was imminent, and that day Horton ordered all available submarines to put to sea.

[1] On 4 June 1940, Jules Verne and all the French submarines assigned to her departed Dundee and proceeded to Brest, France.

[5] At 18:30, Jules Verne and 13 submarines, including Sibylle, got underway from Brest bound for Casablanca, French Morocco, which they reached on 23 June 1940.

On 11 and 12 September 1940, Sibylle, Antiope, Amazone, and their sister ship Amphitrite covered Force Y, a French Navy force consisting of three cruisers and three destroyers, as it arrived at Casablanca from Toulon, France, refueled, and then resumed its voyage to French West Africa.

On 24 September 1940, Sibylle, Amazone, Amphitrite, and Antiope received orders to deploy to French West Africa.

As of 23 October 1940 Sibylle still was part of the 16th Submarine Division along with Amazone, Antiope, and Orphée, but now based in French Morocco.

[5] Operation Torch, the Allied amphibious landings in French Morocco and Algeria, began in the predawn hours of 8 November 1942.

[2] American destroyer USS Bristol reported to have engaged an unidentified submarine with its main guns and with depth charges on 11 November 1942 off Fedala.