Gainesville is a city and the county seat of Hall County, Georgia, United States. As of the 2020 census, the city had a population of 42,296. Because of its large number of poultry processing plants, it has been called the "Poultry Capital of the World." Gainesville is the principal city of the Gainesville, Georgia Metropolitan Statistical Area, which is included in the Atlanta–Sandy Springs–Gainesville, Georgia Combined Statistical Area.