As of the 2010 United States Census, there were 5,813 people, 2,294 households, and 1,560 families living in the county. The population density was . There were 2,879 housing units at an average density of . The racial makeup of the county was 75.8% white, 21.8% American Indian, 0.4% Asian, 0.1% Pacific islander, 0.1% black or African American, 0.3% from other races, and 1.6% from two or more races. Those of Hispanic or Latino origin made up 1.6% of the population. In terms of ancestry, 27.6% were German, 13.0% were Irish, 11.2% were English, 9.8% were Norwegian, and 2.0% were American.