Marshall is a city in the U.S. state of Texas. It is the county seat of Harrison County and a cultural and educational center of the Ark-La-Tex region. At the 2020 U.S. census, the population of Marshall was 23,392. The population of the Greater Marshall area, comprising all of Harrison County, was 65,631 in 2010 and 66,726 in 2018. Marshall and Harrison County were important political and production areas of the Confederate States of America during the American Civil War.