Alan Frederick Lascelles, known as "Tommy", was born on 11 April 1887, the son of Commander Frederick Canning Lascelles and Frederica Maria. He was educated at Hazelhurst preparatory school, Marlborough College and Trinity College, Oxford.

During the First World War, Lascelles served in France with the Bedfordshire Yeomanry (1914-18). He was then appointed Aide-de-Camp to Lord Lloyd, the Governor of Bombay (1919-20). In Delhi he married Joan Thesiger (eldest daughter of the Viceroy, Frederic Thesiger, Viscount Chelmsford) with whom he had three children. Having returned to England in 1920 Lascelles was appointed Assistant Private Secretary to the Prince of Wales (later Edward VIII). He was Secretary to Governor General of Canada (1931-35); Assistant Private Secretary to King George V (1935), and to King George VI, (1936-43), rising to the position of Private Secretary (1943-52) becoming Private Secretary to the Queen (1952-53). He was Keeper of the Royal Archives (1943-1953). Lascelles died on 10 August 1981.

Rupert Hart-Davis was born on 28 August 1907, the only son of Richard Vaughan Hart-Davis and Sybil Mary Cooper, elder sister of 1st Viscount Norwich. He was educated at Stanmore Park, then Eton, and Balliol College, University of Oxford. In 1929 he married (1st), Peggy Ashcroft, then following a divorce, in 1933 he married (2nd), Catherine Comfort Borden-Turner, daughter of Mary Borden and George Douglas Turner, having two sons (Duff and Adam Hart-Davis) and one daughter, Bridget. This marriage also ended in divorce, and in 1964, Hart-Davis married (3rd), Winifred Ruth, daughter of C. H. Ware, and widow of Oliver Simon. She died in 1967, and in 1968 Hart-Davis then married (4th), June (née Clifford), widow of David Williams.

After a brief period in the theatre, during which he studied at the Old Vic (1927-28) and worked as an actor at the Lyric Theatre, Hammersmith (1928-29), Hart-Davis entered the publishing world as an office boy at William Heinemann Limited (1929-31). He then left to become firstly Manager of the Book Society (1932) and then Director of Jonathan Cape Limited (1933-40).

During the war Hart-Davis served in the Coldstream Guards (1940-45). Returning to publishing at the end of the war, he founded his own firm, Rupert Hart-Davis Limited, in 1946, and although the firm enjoyed critical success, it was sold to Heinemann in 1955.

Hart-Davis's publications include: "Hugh Walpole: a biography" (1952); "The Arms of Time: a memoir" (1979); "The Power of Chance: a table of memory" (1991); "Halfway to Heaven" (1998). He was also a highly successful editor, with works including: "The Essential Neville Cardus" (1949); "E. V. Lucas: Cricket all his Life" (1950); "George Moore: Letters to Lady Cunard" (1957); "The Letters of Oscar Wilde" (1962); "Max Beerbohm: Letters to Reggie Turner" (1964); "Max Beerbohm: More Theatres" (1969); "Max Beerbohm: Last Theatres" (1970); "Max Beerbohm: A Peep into the Past" (1972); "A Catalogue of the Caricatures of Max Beerbohm" (1972); "The Autobiography of Arthur Ransome" (1976); "William Plomer: Electric Delights" (1978); "The Lyttelton Hart-Davis Letters", vol. I, 1978, vol. II, 1979, vol. III, 1981, vol. IV, 1982, vol. V, 1983, vol. VI, 1984; "Selected Letters of Oscar Wilde" (1979); "Two Men of Letters" (1979); "Siegfried Sassoon Diaries": 1920-1922 (1981), 1915-1918 (1983), 1923-25 (1985); "The War Poems of Siegfried Sassoon" (1983); "A Beggar in Purple: commonplace book" (1983); "More Letters of Oscar Wilde" (1985); "Siegfried Sassoon: Letters to Max Beerbohm" (1986); "Letters of Max Beerbohm 1892-1956" (1989). Hart-Davis died on 8 December 1999.