The collection consists of files of printed ephemera such as biographical data, broadsides, brochures, bulletins, clippings, flyers, leaflets, obituaries, pamphlets, reprints, unpublished papers and other documents relating to a broad range of individuals connected in some way with the Abraham Lincoln Brigade. The bulk of the collection consists of files on individual Lincoln Brigade volunteers, but there are also files on Spanish participants in the Civil War, International Brigade volunteers from other nationality groups, journalists, visitors to Spain, and historians and others who have studied the conflict. (Some files include non-print items such as donor correspondence, typed notes, etc.)