The term Cowlitz people covers two culturally and linguistically distinct indigenous peoples of the Pacific Northwest; the Lower Cowlitz or Cowlitz proper, and the Upper Cowlitz / Cowlitz Klickitat or Taitnapam. Lower Cowlitz refers to a southwestern Coast Salish people, which today are enrolled in the federally recognized tribes: Cowlitz Indian Tribe, Quinault Indian Nation, and Confederated Tribes of the Chehalis Reservation. The Upper Cowlitz or Taitnapam, is a Northwest Sahaptin speaking people, part of the Confederated Tribes and Bands of the Yakama Nation.
Their traditional homelands are in western Washington state in the United States.