- Amon W. Updike Correspondence, 1861/18651
- Andrew Given Family Correspondence, 1859/18861
- Andrew J. Lewis Correspondence, 1863/18651
- Anna Lee Letter, 18611
- Ansil T. Bartlett Letter,, 18651
- Anthony K. Simmons Letter, 18621
- Archibald Atkinson, Jr., Memoir, 19001
- Army of the Potomac Under General Grant, 19631
- Arthur G. Sinclair Letters, 18641
- Asa Baldwin Correspondence, 1864/18651
- Asa P. Blunt Letter,, 18641
- Assault on Fort Sanders, 18911
- Atwell W. Robertson Letter,, 18631
- August Dietz Civil War Collection,, 1862/19091
- Augustus Smith Family Collection, 1864/19261