| United States|
| Southwestern Washington|
200 Cowlitz people (1990)
maybe 2 speakers in 1990
the 110 listed in 2010 census are not native speakers
The Cowlitz language is a member of the Tsamosan branch of the Coast Salish family of Salishan languages.
Cowlitz language Wikipedia
The Cowlitz people were originally two distinct tribes: the Lower Cowlitz and the Upper Cowlitz. Only the Lower Cowlitz spoke Cowlitz; the Upper Cowlitz, a Sahaptin tribe, spoke a dialect of Yakama.
Cowlitz is most similar to Lower Chehalis, another Tsamosan language, although it does contains some oddities, such as the word for one, utsus (in contrast to the Lower Chehalis paw).