Tattnall County is a county located in the southeast portion of the U.S. state of Georgia, located within the Magnolia Midlands, a part of the Historic South region. As of the 2020 census, the population was 22,842. The county seat is Reidsville. Tattnall County was created on December 5, 1801, from part of Montgomery County, Georgia by the Georgia General Assembly.

Montgomery County is a county located in the central portion of the U.S. state of Georgia. As of the 2020 census, the population was 8,610. The county seat is Mount Vernon. Montgomery County is part of the Vidalia, GA micropolitan statistical area.