 He served in World War II, commanding the 14th Battalion of the Sherwood Foresters (Nottinghamshire and Derbyshire Regiment) in Italy in 1943 and the 66th Infantry Brigade from 1944–45.He was awarded the DSO in February 1945, Mentioned in Despatches on 11 January 1945 and made an Honorary Brigadier in 1945.In 1950, Redmayne entered the Commons as Conservative MP for Rushcliffe.