Stephenville is a city in and the county seat of Erath County, Texas, United States. The population was 17,123 at the 2010 census. Founded in 1856, it is home to Tarleton State University. Stephenville is among several communities that call themselves the "Cowboy Capital of the World".HistoryStephenville is named after John M. Stephen, who settled there in 1854 and donated the land for the townsite laid out by George B. Erath when the county was organized in 1856. In the first two years of its settlement, the townsite was successful; by 1858 the population reached 776. However the townsite was located in Comanche territory and raids were common. Also the hardships of the American Civil War forced citizens to leave. The population declined until 1871 when it grew after Stephenville became an agriculture and livestock center. Coal mining also became important to the area in 1886 and was a major segment of the economy for the following three decades.Stephenville was incorporated in 1889, with the arrival of the Fort Worth and Rio Grande Railway. In the 1890s, many of the buildings around the town square were built, Tarleton State University opened, and the community's two newspapers merged to become the Empire-Tribune, which is still in existence. In February 1907 the Stephenville North and South Texas Railway was chartered by Stephenville and Hamilton business interests which later sold the line in 1910 to the historic St. Louis Southwestern Railway of Texas system. In the 20th century industry became an important part of Stephenville, and the population has steadily increased since the 1920s.