[2] The county was established in 1865 as one of the original nine counties of Montana, and named in 1882 after Pierre Chouteau Jr., a fur trader who established a trading post that became Fort Benton, which was once an important port on the Missouri River.

Chouteau County is home to the Chippewa-Cree tribe on the Rocky Boy Indian Reservation.

The Bear Paw Mountains rise in the northeast and the Little Rockies and the Highwood Ranges are in the southeast.

The United States Census Bureau, for population data analyses of unorganized rural areas, the following Census-designated places, or CDPs, in addition to the organized communities listed elsewhere in this article.

[citation needed] As of the 2010 census, there were 5,813 people, 2,294 households, and 1,560 families living in the county.

[10] It is located in the heart of the "Golden Triangle", which produces about 45% of Montana's annual wheat crop.