Chehalis (i/ʃəheɪlɨs/ US dict: shə·hā′·lĭs) is a city in Lewis County, Washington, United States. The population was 7,259 at the 2010 census. It is the county seat of Lewis County.
Chehalis began as a settlement around a warehouse beside a railroad track in 1873, when the Northern Pacific Railroad built northward from Kalama to Tacoma, and ignored Claquato, then the county seat three miles to the west. Some settlers decided that, if the railroad would not go to the county seat, the county seat must go to the railroad. By 1874, a store was added to the warehouse, several houses were constructed, and the county seat was moved to the new settlement, leaving Claquato little more than a historical landmark. The new town was first named Saundersville, for S.S. Saunders, on whose donation land claim it was founded. In 1879, the name was changed to Chehalis, named after the Chehalis people. Chehalis was officially incorporated on November 23, 1883.
Logging soon began in the nearby forests. Lumber workers of Scandinavian, Anglo-Saxon, and Scots-Irish descent arrived, and remained to settle in the neighboring valleys. In 1940, the chief local industries were: dairying, poultry raising, fruit growing, milk condensing, fruit and vegetable packing, brick and tile manufacturing, coal mining, portable house manufacturing, and fern shipping. The 1940 population was 4,857. (Washington - A guide to the Evergreen State, WPA American Guide Series, Washington State Historical Society, 1941).