- Albert L. Sturm Papers, 1904/19881
- Alfred C. Payne Collection, 1917/20031
- Ann A. Hertzler Collection, 1863/2013, bulk 1974/20001
- Arthur M. Squires Papers, 1888/1987, bulk 1940/19871
- Byron Nelson Cooper Papers, 1925/19711
- C. David Loeks Papers, 1947/19971
- C. Eugene Rowe Papers, 1949/19871
- Carol M. Newman, Jr., Papers, 1930/19871
- Charles A. Kennedy Papers,, 1963/19871
- Charles Burchard Collection, 1935/19891
- Charles S. Worley, Jr., Collection, 1950/19821
- Clarence Trent Papers, 1958/19911
- Clinton H. Cowgill Collection, 1916/19771
- Dan H. Pletta Papers, 1942/19961
- Dayton M. Kohler Papers, 1889/19711