Context : The 43rd (Wessex) Reconnaissance Regiment (The Gloucestershire Regiment) (43 Recce) was a regiment of the British Army's Reconnaissance Corps, itself part of the Royal Armoured Corps, during World War II. It fought in North West Europe with the 21st Army Group in 1944--1945. 
Question : What army did 43rd (Wessex) Reconnaissance Regiment serve in?
British Army