Edmund O'Donnell Colley Grattan, the son of Colley Edmund George Grattan, a barrister, was born on 2 February 1910 at Bournemouth. His mother Winifred Katharine Wyndham Barnard was the daughter of Sir Herbert Barnard, a banker, whilst his father's side of the family was descended from Henry Grattan,

John Douglas Fergusson was born on 5 December 1909 at Great Malvern, Worcestershire, the son of John Newberry Fraser Fergusson, FRCS Edinburgh, radiologist at York County Hospital. He was educated at St Peter's School, York, and St John's College, Cambridge, where he was college prizeman and scholar