- 19th Century Virginia albumen photographs, 1880/18991
- 6th Battery of Binghamton, N.Y. Veterans minute book, 1871/19111
- A. H. Hand Papers, 1835/20091
- A. K. Leake Papers, 1872/19402
- A. Willis Robertson Papers, 1921/1988, bulk 1946/19663
- A.J. Lawrence Account Book, 1857/18831
- Abraham Rudisill diary, 1875/18861
- Adam Empie Papers, 1811/2004, bulk 1811/18502
- Adams Papers, 1782/18901
- African American Family Photographs, 1880/19601
- Alabama Collection, 1823/18931
- Albert C. Swindler Papers, 1862/1929, bulk 1862/18641
- Alexander Brown Papers (I), 1815/19108
- Alexander Brown Papers (II), 1748/190011
- Alexander Hamilton, Jr. Letters, 1832/18331