- Galt Papers (I), 1745/18929
- Galt Papers (III), 1750/19919
- Gaspard Monge Portrait Print, 1746/18181
- Genealogical Society of Southwestern Pennsylvania, Collector, Material regarding Monongalia County Unrecorded Wills, 1726/17811
- George Couchman Family Papers, 1765/19351
- George Mason Papers, 1706/18582
- George Mason University Student Government records, 1968/20191
- George Washington Papers [in part: photostats, printed copies, typescripts], 1755/19322
- George Washington collection, 1654/179910
- George Weedon and Charles Washington Ledger, 1772/17732
- George Whipple Ledger, 1764/18141
- Gideon Macon Family Charts, 1602/19951
- Governor Arch A. Moore Jr. papers, 1950/19891
- Great Bethel Baptist Church (Uniontown, Pa.) Records, 1770/19031
- Gregory A. Prince Mormon Studies Collection, 1813/20201