To pre-empt the potential Italian threat, Georges Leygues and other French warships were moved to Mers-el-Kebir (now Oran) on 24 April 1940.

The 3rd and 4th Cruiser Divisions, including Georges Leygues avoided the destruction of the French Fleet at Mers-el-Kebir and eventually put into Toulon.

Montcalm and Georges Leygues outran the Allied ships and returned to Dakar, where they helped to defend the port against the unsuccessful British and Free French attack (Operation Menace) on 23–25 September 1940.

Early in 1943, she began Atlantic patrols from Dakar, and on 13 April, she intercepted the German blockade runner Portland, which was scuttled by her crew.

Georges Leygues was refitted at Philadelphia Naval Shipyard, from July until October 1943, removing the aircraft installations and adding light anti-aircraft weapons.

In 1956, she took part in the Suez Crisis, during which she led a group of French warships providing fire support for Israeli ground forces in the Gaza Strip.