Raymond Purvis was born in Southampton on 30 December 1904, the second child and younger son of a consultant surgeon, William Prior Purvis, MD, MS, FRCS, and of Dora Raymond, daughter of Walter Raymond, a Somerset author. His paternal grandfather and great grandfather were also medically qualified.

Arnold Guy Harsant was born in London on 16 November 1893 and educated at St Paul's School, Kensington. He gained a scholarship to the London Hospital, qualified with the Conjoint Diploma in 1916, and that year was granted a regular commission in the RAMC. He served in the Salonika Campaign from 191