The eldest son of Walter Rea, a Liberal politician, and his first wife, Evelyn, Rea was educated at Westminster School, and then at Christ Church, Oxford University, where he graduated BA and later MA, and lastly at the University of Grenoble.

In 1918, during the closing stages of the First World War, he served as a second lieutenant in the Grenadier Guards.

During the Second World War he returned to the British Army and served as personal staff officer to Brigadier Colin Gubbins, Head of the Special Operations Executive, a key British intelligence and guerrilla operations agency.

Rea married Lorna Smith (died 11 December 1978) on 7 April 1922.

Ann Felicity Rea (born 1923) served in the WRNS in the Second World War[1] and married SOE veteran Malcolm Munthe in 1945.