Shortly after the outbreak of the Second World War, in September 1939, Anderson led the 11th Brigade, still part of the 4th Division, overseas to France where it became part of the British Expeditionary Force (BEF). Anderson saw service with the BEF throughout the "Phoney War" period and during the Battle of France in May 1940 and, when Major-General Bernard Montgomery, General Officer Commanding (GOC) of the 3rd Infantry Division, was promoted to command II Corps during the evacuation from France, the departing II Corps GOC, Lieutenant-General Sir Alan Brooke, chose Anderson, of whom he thought highly, to take temporary command of Montgomery's 3rd Division.