1992-1995 Additions: 138 volumes of his diaries, 1920-1994, have been added, as well as 12 letters from W.A. Craigie concerning new entries for the Oxford English Dictionary, 1 drawing in the style of John Leech, 2 19th century drawings, the manuscript of his "Young John of Gaunt; a poem in fourteen cantos", 22 engraved American portraits, 5 maps of the American Civil and Revolutionary Wars, 3 scrapbooks, World War I to 1976, his commonplace book, 1927-1990, several of his published books, and "The Sheriff's Prisoner", an autobiographical account of his 8 months in Brixton Prison for Obscene Libel on the publication of "Guido and the Girls", along with letters and documents re. this case.

Collection of 290 letters and documents (150 autograph letters signed, 140 documents and receipts), dated 1860s-1890s, written to and about New York financier and author John Austin Stevens and his son.

Approximately 12,000 letters to Allan Nevins from various correspondents including James Truslow Adams, Franklin Delano Roosevelt, Harry S. Truman, Willa Cather, Frances Folsom Cleveland, Van Wyck Brooks, Robert Frost, Newton D. Baker, Archibald MacLeish, John D. Rockefeller, Jr., Carl Sandburg, and Henry Wallace; notes and typescripts for Nevins' books including Emergence of Lincoln, The Ordeal of Democracy, Rockefeller, and History and Historians, with notes by editor Ray A. Billington; miscellaneous transcripts, clippings, newspapers, and photographs. Also, autograph letters and manuscripts by presidents, Civil War figures, financiers, politicians, and authors. There are also the Brand Whitlock World War I Diaries and letters to him by such people as Herbert Hoover, Gen. John J. Pershing, and others.