East Mountain is on Farm Road 1845 eleven miles southeast of Gilmer in southeastern Upshur County. It was established in the 1870s near a small rise named East Mountain. A local school began operating in the mid-1870s, and a Primitive Baptist church was organized around the same time. Sam Salter settled in the area in the late 1870s and built a horse-powered cotton gin; a short time later Thomas Wells built a steam cotton gin and sawmill. A post office under the name Savannah was opened in 1902 with H. B. Jones as postmaster. It was closed in 1905, and the name of the town was changed to East Mountain a short time later. Oil was discovered in the 1930s, and a number of local families quickly became wealthy. At the height of the oil boom the school and all of the town's churches had producing wells. By the mid-1930s East Mountain had a three-teacher school, three churches, a store, and a number of houses. In 1940 the estimated population was seventy-five. In the mid-1960s East Mountain had five churches, a large district school, and two cemeteries. In the 1980s the town served as a commercial center for area farmers and ranchers and as a bedroom community for nearby Longview. The population was 762 in 1990 and 580 in 2000.