Professor. Personal correspondence (1897–1957); correspondence with Campbell’s relatives (1822–1896); correspondence with publishers and literary agents (1920–1958); literary manuscripts (circa 1914–1957); diaries, notebooks, and journals (1901–1926); and business papers (circa 1925–1959) regarding Campbell’s writings on the West, Indians, and Oklahoma, with emphasis on transportation, fortifications, cowboys, wars and battles, criminals and outlaws, and American Indian chiefs, along with original Indian art by Carl Sweezy. [Boxes 104 through 121 of this collection are available online at the OU Libraries website.]