Sweetwater grew from a railroad stop into the county seat of Nolan County

Nolan County was formed from earlier Texas territory in 1876. It was officially organized in January 1881. The county is named for Philip Nolan. He was an Irish-born adventurer who explored Texas in the late 1700s. Sweetwater became the county seat in April 1881. That happened right after the Texas and Pacific Railway came through.

The early economy ran on cattle ranching. In the early 1900s, cotton farming took over. Then in 1939, petroleum was discovered. Oil production became a major part of the local economy. Today the area is best known for wind energy. The Handbook of Texas, published by the Texas State Historical Association, has a full history of the county and of Sweetwater.