Correspondence, lectures, drafts of books and articles, clippings, and other papers of Pennell and his wife, Elizabeth Robins Pennell, relating to James McNeill Whistler, Joseph Pennell's career as an artist and author, and family affairs. Includes a record of artwork in the field of government propaganda during World War I. Papers of Charles Godfrey Leland, uncle of Elizabeth, include family correspondence; journals (1892-1899); writings; and memoranda relating to to Leland's career as an author and philologist, his studies and travels in Europe, religion, and New England Indians. The Pennells' correspondents include Elmer Adler, J.M. Barrie, Paul Wayland Bartlett, Ford Madox Brown, Timothy Cole, Royal Cortissoz, Walter Crane, Charles Deschamps, Théodore Duret, Henri Fantin-Latour, John F. Flanagan, Cass Gilbert, Edmund Gosse, Charles James Whistler Hanson, Childe Hassam, Henry James, Robert Underwood Johnson, John Lane, Leila Mechlin, A. Edward Newton, Agnes Repplier, Alice Caldwell Hegan Rice, Auguste Rodin, William Edwin Rudge, Linley Sambourne, John Singer Sargent, John Charles Van Dyke, and James McNeill Whistler.

Correspondence and legal papers of Whistler and clippings concerning Whistler. Subjects include the 1892 Whistler exhibition in the Goupil Gallery, London, England; the Whistler-Ruskin litigation; and Whistler's friends, career, and business affairs. Papers of Anna Matilda McNeill Whistler include a diary and correspondence with Margaret Hill, Mary Eastwick, and others. Whistler's correspondents include Edward Coley Burne-Jones, William Heinemann, Thomas Jekyll, Edward G. Kennedy, Frederick Richard Leyland, Joseph Pennell, Valentine C. Prinsep, James Anderson Rose, Dante Gabriel Rossetti, William Michael Rosetti, Frederick Sandys, David Croal Thomson, Virginia Vaughan, and the Heinemann (Firm) and Morris & Co. (London, England).