April 1931 she entered service with La Marine National and was assigned to the First Light Division of the First Squadron at Toulon. She carried out normal peacetime operations until 1935. In February 1935 she proceeded to Lorient and started a major refit on 16 February which lasted until January 1936. On 12 April 1937 the First Light Division was renamed as the First Cruiser Division and consisted of Colbert, , and . On 27 May 1937 she was present at the Great Naval Review at Brest following Naval Maneuvers with the Mediterranean and Atlantic Squadrons. Upon returning to the Mediterranean she was assigned to the International Patrol off the south coast of Spain. The international Patrol had been formed to protect merchant shipping from piracy instituted by unknown (probably Italian) submarines. Wartime service At the beginning of the war she was in Toulon. In December she sailed with for Bizerte, Tunisia. On 8 December after forming the Second Cruiser Division both ships sailed to monitor shipping as far east as Beirut. She returned to Bizerte on 28 December. In January 1940 she joined Force Y arriving at Dakar on 30 January to replace Force X. The first sortie was from 18 to 28 February. She was due to participate in the second sortie from 6 to 18 March, but was sent on 7 March to reinforce Force X consisting of the battleship and cruiser Algérie escorting gold to Canada. She returned to Dakar when completed. Force Y left Dakar on 11 April 1940 and returned to Toulon. On the night of 13/14 June she participated in Operation Vado, the bombardment of Genoa and Vado, Italy by the Third Squadron. The Vado Group included the cruisers Foch and Algérie and the Genoa Group included the cruisers Dupleix and Colbert. The bombardment cause little damage as Group Genoa fired at the wrong target and half of Group Vado shells fell into the sea. The squadron returned to Toulon by mid-day on 14 June. Foch suffered a steering malfunction but returned safely. On 25 June the Franco-German Armistice took effect and La Marine National ceased all offensive operations. On 3 July with the ill-conceived British attack on Mers-el-Kébir, the battleship had escape undamaged, the Fourth Cruiser Division had sailed from Algiers to Oran. The Fourth failed to link up with Strasbourg so they sailed for Toulon. Algérie, Foch and Colbert with twelve