[2] Under the command of Lieutenant de vaisseau Jaume from August 1939,[3] Junon operated from Oran and Casablanca early in the war, finally sailing to France in March 1940 for refitting.

[5] On 3 July 1940 Junon (along with all other French naval vessels in British ports) was boarded by Royal Navy troops as part of Operation Catapult.

[4] She was transferred to the Free French Naval Forces on 27 July,[4] but not recommissioned until February 1941, under the command of Capitaine de corvette Jean-Marie Querville.

In October she made three attacks on enemy ships in the Vestfjorden, at least one of which (the Nordland) was successful, and on 13 November picked up several agents and their radio equipment in the Melfjorden.

[1] On 1 March 1943 command of Junon was assumed by Lieutenant de vaisseau Étienne Schlumberger, and in February 1944, after a long refit, she sailed for Algiers.