The regiment mobilized The Fort Garry Horse, CASF, on 1 September 1939. It was redesignated as the 10th Armoured Regiment (The Fort Garry Horse), CASF, on 11 February 1941, the 10th Armoured Regiment (The Fort Garry Horse), CAC, CASF, on 15 October 1943 and the 10th Armoured Regiment (The Fort Garry Horse), RCAC, CASF, on 2 August 1945. The regiment embarked for Britain in November 1941.
The regiment landed in Normandy on 6 June 1944, as a part of the 2nd Canadian Armoured Brigade, in support of the 8th Infantry Brigade, 3rd Canadian Infantry Division, and fought in North-West Europe until the end of the war. The overseas regiment was disbanded on 31 January 1946