Cooper was educated at the prep school Arnold House School, St John's Wood, London, at Lancing College on the South Downs, and later studied languages in Grenoble in the French Alps and at a language school at San Sebastian in Northern Spain. It was here, with the Spanish Civil War raging around him, that he was shot through the arm one evening by a sniper's bullet, while on a mission to purchase cigarettes before dinner. The Royal Navy subsequently came to his rescue, gave him medical attention and dropped him off across the French border at St Jean de Luz.