John McGill was a lawyer in Urbana, Virginia (in Middlesex County), and flourished between 1827 and 1848. The collection consists of incoming letters, financial records, records of the William Shepherd estate, and J. Hopkins Brothers and Company records all ranging in date from 1827 to 1849. The bulk of the incoming letters are from Baltimore merchants.

The Johns Hopkins University collection of Maryland African American history and culture is an artificially assembled collection which spans from the 18th to the 20th century. The collection consists of materials selected by the curators of Special Collections.

The Johns Hopkins University collection of slavery records is an artificially assembed collection by the curators of Special collections, with materials that span from the 18th to the 19th century and primarily document the enslavement of African Americans in the United States.