Maidu

Maidu was spoken in the United States, in northeastern California, in the Sierra Nevada foothills and the upper Feather River valley, around Susanville, Quincy, and Greenville.
Maidu belongs to the small Maiduan family, which also includes Konkow and Nisenan, and has been grouped in the proposed Penutian stock. The last fluent native speakers died in the early 21st century, and it is now considered extinct as a first language, though community members are working to revive it from recordings and written records.