He was born in Long Eaton, Derbyshire and grew up in Chatham. His education was interrupted by the Second World War and he entered the Royal Navy in 1942. He served on HMS "Uganda", where he helped support the landing in Sicily and at Salerno. In 1944, he became a cypher officer and was put in charge of shore bases during the Normandy landings. After serving in the Far East he was demobilised in 1946. Mingay married in 1945.