The collection consists of papers gathered and generated by Ruth E. and Edward M. Brecher while researching the life of William Francis Mannix (1870?-1920), a journalist, soldier of fortune, grafter, and literary forger, for a proposed biography that was never completed. Included are manuscript drafts; correspondence with Ralph D. Paine, Mabel Scudder, Mrs. Mannix, and others about Mannix; copies of his birth, marriage, and army records; and other letters, notes, and clippings on Mannix's background, psychopathic personalities, and literary forgeries.

Also present is material concerning the book Memoirs of Li Hung Chang (1913), edited by Mannix, which later proved to be a fabrication, and about a collection of love letters supposedly written by Abraham Lincoln to Ann Rutledge, published by the Atlantic Monthly in 1929, and later thought to have been forged by Mannix.