 The latter name is for a U.S. Army fort established in 1860 before the town was founded, "ts-a-lis" is the Lower Chehalis word for Westport, meaning "place of sand".Early explorers pronounced the word "Chehalis" and gave this name to the river and the people living up river who later became the Chehalis people or "People of the Sands".The area was used regularly during the summer by local Native American tribes (most likely the Shoalwater Bay Tribe, comprising Willapa Chinook and Lower Chehalis people) before Thomas Barker Speake and his family arrived early in the summer of 1857.