Balfour was born in 1894 in London, and educated at Eton and New College, Oxford. He went to Freiburg on July 27th 1914 to study German and was interned at Baden-Baden at the outbreak of the First World War, and was later transferred to Ruhleben, where he remained a prisoner between November 1914 and November 1918.Sir John Balfour was the son of Charles Balfour MP and Lady Nina Balfour, and was colloquially known as "Jock". After attending Eton and Oxford he was caught out in Germany and sent to Ruhleben, where he spent the war studying languages. After the war, Balfour had a very succesful diplomatic career, including stints aas the head of the American department in WW2 and a posting in Moscow (being a fluent Russian speaker). In 1933 he married Frances van Millingen, who was appoointed CVO in 1969, after a spell as lady in waiting to Princess Marina, the Duchess of Kent, from 1961-1968.