As of the 2000 United States Census, there were 10,620 people, 3,581 households, and 2,614 families in the county. The population density was 4 people per square mile (2/km2). There were 4,044 housing units at an average density of 2 per square mile (1/km2). The racial makeup of the county was 40.93% White, 0.05% Black or African American, 55.75% Native American, 0.43% Asian, 0.05% Pacific Islander, 0.25% from other races, and 2.53% from two or more races. 1.23% of the population were Hispanic or Latino of any race. 12.6% were of Norwegian and 11.5% German ancestry. 94.8% spoke English and 3.4% Dakota as their first language.