South Gate is a city in Los Angeles County, California. It is part of the Gateway Cities region of southeastern Los Angeles County. As of January 1, 2009, the city had a total population of 102,770. The "City of South Gate" was incorporated on January 20, 1923, by the Los Angeles County Board of Supervisors. In 1990, South Gate was one of ten U.S. communities to receive the All-America City Award from the National Civic League.