Roswell is a city in northern Fulton County, Georgia, United States. At the official 2020 census, the city had a population of 92,883, making Ros…Roswell is a city in northern Fulton County, Georgia, United States. At the official 2020 census, the city had a population of 92,883, making Roswell the state's ninth largest city. A suburb of Atlanta, Roswell has an affluent historic district.