As of the 2010 United States Census, there were 10,425 people, 3,553 households, and 2,548 families residing in the county. The population density was . There were 4,063 housing units at an average density of . The racial makeup of the county was 60.4% American Indian, 35.8% white, 0.4% Asian, 0.1% black or African American, 0.2% from other races, and 3.0% from two or more races. Those of Hispanic or Latino origin made up 1.3% of the population. In terms of ancestry, 20.0% were Norwegian, 16.3% were German, 6.1% were Irish, and 1.3% were American.