The John Gloucester Memorial and Historical Society was established in 1910 and is dedicated to preserving the history of First African Presbyterian Church. The first black Presbyterian congregation in the United States, First African Presbyterian was established in Philadelphia, Pennsylvania, in 1807 with former slave Rev. John Gloucester as its inaugural pastor. The church is now located at 42nd Street and Girard Avenue in Philadelphia. The John Gloucester Memorial and Historical Society manages approximately 20 linear feet of archival materials dating from 1863 to the present, although the bulk of the materials date from 1950 or later. The collection consists primarily of records of First African Presbyterian Church such as minutes, membership materials, and photographs. There are also some secondary materials about the church, its members, and various organizations and topics that were collected by church members. Of interest are photographs taken by John W. Mosley, a self-taught photographer known for capturing images of Philadelphia's African American community. He worked for the "Philadelphia Inquirer" but also served as official photographer of First African Presbyterian Church.