The 1/6th and 1/7th battalions of the regiment were both assigned to the 147th Infantry Brigade, alongside the 1/5th West Yorkshire Regiment, which itself was part of the 49th (West Riding) Infantry Division. The brigade did not see service with the rest of the division in the Norwegian Campaign, but were instead sent to Iceland after it was invaded in 1940, and remained there until May 1942 when it was transferred back to the United Kingdom. On 28 February 1943, both battalions lost the '1/' prefix, becoming, simply, the 6th and 7th battalions, respectively. They both landed in Normandy on 12 June 1944 shortly after the D-Day landings of 6 June. They fought in the Battle of Normandy as part of the British Second Army in its attempts to capture the city of Caen. In particular, the 6th Battalion was severely mauled during Operation Martlet and, due to the heavy casualties sustained, was returned to the United Kingdom and disbanded, most of its men being sent to the 7th Battalion. They were replaced in the brigade by the 1st Battalion, Leicestershire Regiment. The 7th DWR continued to fight in the Normandy Campaign in the Second Battle of the Odon, and clearing the Channel Ports in Operation Astonia.