- C. Barrett Graham papers, 1967/20161
- Carl von Lang-Puchhof thoroughbred racehorse portrait album, 1891/19111
- Charles Beseler Lantern Slide Company salesman sample catalogs, 1890/19291
- Charles E. Kilbourne personal papers, 1898/19632
- Charles T. Smith photographs, 1880/2007, bulk 1990/19991
- Chinese Student Organization (CSO) records, 1997/20081
- Clinton K. Curtis photograph albums, 1880/18891
- Connie Smith family photograph album, 1950/19801
- Coray S. Brown family photograph collection, 1910/19601