The 1/5th Battalion was a 1st-Line Territorial Army (TA) unit serving in the 42nd (East Lancashire) Infantry Division with the 1/6th and 1/8th battalions in the 125th Infantry brigade. They were sent to France in April 1940 to join the rest of the British Expeditionary Force (BEF) and fought in the Battle of Dunkirk and were evacuated to Britain. In 1941, the battalion was converted to armour as the 108th Regiment Royal Armoured Corps (Lancashire Fusiliers). Units converted in this way continued to wear their infantry cap badge on the black beret of the Royal Armoured Corps.