County Origins
Erath County Was Founded in 1856 and Named for a Texas Surveyor
Erath County was carved out of Bosque and Coryell counties in 1856 and named after George B. Erath, a surveyor who mapped much of this part of Texas.
George B. Erath was a surveyor who helped map Central Texas in the mid-1800s. When the Texas Legislature created Erath County in 1856, it was named in his honor. The county seat, Stephenville, got its name from John M. Stephen, who donated land for a courthouse and townsite.
Early settlers arrived in the mid-1850s, but conflict with Comanche raiding parties kept population growth slow until the 1870s. Once raids ended around 1873, the county grew quickly. Cotton farming dominated from the 1870s through the early 1900s. The economy later shifted to dairy, beef cattle, and peanuts. The Handbook of Texas at the Texas State Historical Association has the full county history.
Source to confirm: TSHA Handbook of Texas — Erath County