The 1st Battalion landed in France in September 1939 as part of the 12th Brigade in the 4th Infantry Division for service with the British Expeditionary Force (BEF). The battalion later transferred to the 153rd Brigade of the 51st (Highland) Division and was captured at St Valery-en-Caux during the Battle of France. It was reformed from reserve units of the 9th (Highland) Infantry Division in August 1940 and moved to North Africa in August 1942 where it fought at the Second Battle of El Alamein in October 1942 and then continued to fight in the Tunisian Campaign before it took part in the Allied invasion of Sicily in July 1943. It also took part in the Normandy landings in June 1944, the Battle for Caen later that month and the Battle of the Falaise Pocket in August 1944. It later saw action at the Battle of the Bulge in January 1945, Battle of the Reichswald in February 1945 and the crossing of the Rhine in March 1945.