Carthage is located south of Marshall on US 59, US 79, and Hwy 315, where it is the seat of Panola County. It is near the Sabine River and the Texas/Louisiana state line.
In 1920 Carthage had a population of 1,366. The community expanded steadily afterward, spurred by the growth of the oil and gas industry and general commerce in the area. In 1940 the population had risen to 2,178, and by 1980 it had reached 6,477. The town had a shopping mall and a renovated downtown, as well as a cup company and a chicken-processing plant. In 1990 the population was 6,496.
