Correspondence, including: Letters to William Archer, Add. MS 45291; correspondence with Sir Sydney Cockerell, Add. MS 52717; Correspondence with Macmillans, Add. Ms 55012; letters to T. Watts-Dunton Ashley, Ms 822, British Library, St Pancras
Correspondence with Robert Bridges, Gilbert Murray and others, Bodleian Library, Oxford
Diary and correspondence with John St Loe Strachey, Parliamentary Archives of the United Kingdom, Palace of Westminster (Houses of Parliament), London
Correspondence and mss, Cambridge University Library, Cambridge
Correspondence and mss, Brotherton Collection, University of Leeds, Leeds
Correspondence with Austin Dobson, London University Library, London.
Travel journal; correspondence with Sir Graham Balfour; and correspondence with Lord Haldane; National Library of Scotland, Edinburgh
Correspondence with Edward Dowden, Trinity College, Dublin
Letters as sponsor to Royal Literary Fund, Royal Literary Fund, London
Letters to the Royal Society of Literature, Somerset House, London
Letters to Austin Dobson; letters to A. C. Swinburne; correspondence with Sir Hamo Thornycroft; and letters to Theodore Watts-Dunton; University of Leeds