Gregg County is a county located in the eastern part of the U.S. state of Texas. As of the 2020 census, its population was 124,239. Its county seat is Longview. The county is named after John Gregg, a Confederate general killed in action during the American Civil War.
Gregg County is part of the Longview, Texas metropolitan area and the Longview–Marshall, Texas combined statistical area. Discovery of oil near Kilgore in October 1930 was the beginning of an oil boom that attracted workers to the county and expanded the population by more than 500% by 1940, according to the census. By that time, the economy had stabilized, but the East Texas Oil Field, extending into five counties, has continued to be important to the county and region's economy.
