Collection
- Busbey papers, 1838-1928 (majority within 1848-1903)1
- Charles E. Shryock journal, 1861-18621
- Charles F. Penley captured letters, 1864, 19151
- Charles H. F. Daigneault and Ren W. Philbrick drawing book, 1901-1905 (bulk 1904)1
- Charles H. Foster collection, 1898-19671
- Charles M. Maxim papers, 1864-18701
- Charles S. May papers, 1849-19041
- Clark-Whedon papers, 1863-18651
- Clement Abner Boughton papers, 1839-1906 (majority within 1861-1864)1
- Clinton H. Haskell Civil War collection, 1841-18951
- Connecticut Comptroller records, 1862-18631
- Cruikshank-Dawley papers, 1841-18901
- Cyrus W. Newton letters, 1862-18641
- Daniel E. Hedden diary, 1862-18631
- David Ballenger typescripts, 1858-1888 (majority within 1861-1865)1
- Devereux papers, 1822-18721
- Dixon family papers, 1833-1875 (majority within 1862-1865, 1873-1875)1
- E. C. Tillotson papers, 1862-19081
- Eagleswood Academy photograph album, 1863-ca. 18901
- Ebenezer Hoar papers, 1852-18751