The Gros Ventre, Atsina people, the "White Clay people," are a Algonquian-speaking Native American people located in north central Montana.

Today the Gros Ventre people are enrolled in the Fort Belknap Indian Community of the Fort Belknap Reservation of Montana, a federally recognized tribe, that also includes Assiniboin people, the Gros Ventre's historical enemies.

In 1862, Jesuits came to Fort Belknap to convert the Gros Ventre people to Roman Catholicism. Consequently, their traditional ceremonies took second place.

However, in time their traditions revived and two sacred ones took precedent: that being the two sacred pipes. The Feathered Pipe and The Flat Pipe remain central to the traditional spiritual beliefs of the Gros Ventres.