The Rev. William Mumford Baker presided over the organization of this congregation in 1854 at the Round Rock home of Richard and Mary Agnes (Cooper) Sansom. By 1856, the church was meeting in Georgetown, where C.A.D. Clamp deeded a site at 4th and Myrtle Streets for a sanctuary and one of the town’s first schools. In 1866, following the Civil War, the membership split into separate Northern and Southern congregations. The division continued into the 1890s, when the northern church disbanded and sold the present building to the southern congregation. Georgetown Presbyterians have met in this building since 1873. The northern and southern denominations reunited in 1983 as Presbyterian Church (USA).