- A. E. Dick Howard papers, 1928/20171
- A. H. Hand Papers, 1835/20091
- A. Willis Robertson Papers, 1921/1988, bulk 1946/19663
- Abner Johnson Leavenworth Papers, 1825/18611
- Abraham Grove Account Book, 1815/18501
- Absalom See Account Books, 1854/18691
- Adam Rinica and George Rinica Account Book, 1822/18481
- Adams Papers, 1782/18901
- Addie Rogers Bound Sheet Music Collection, 1827/18602
- Administration records collection, 1776/19765
- Advisory Committee Research Collection, 1772/20175
- Aileen Shafer, Collector, Material regarding African-Americans, 1829/18844
- Alabama Collection, 1823/18931
- Albert Frederick Wilson papers, 1840/19342
- Albert R. Gallatin papers, 1795/18281