Major highways

Adjacent counties

Protected areas^[5]

• Cross Ranch State Park

Lakes^[5]

• Mandan Lake
• Nelson Lake

2020 census

As of the census of 2020, there were 1,877 people.

2010 census

As of the census of 2010, there were 1,846 people, 756 households, and 554 families in the county. The population density was 2.55 people per square mile (0.98 people/km²). There were 905 housing units at an average density of 1.25 units per square mile (0.48/km²). The racial makeup of the county was 97.3% white, 1.5% American Indian, 0.2% black or African American, 0.2% Asian, 0.2% from other races, and 0.7% from two or more races. Those of Hispanic or Latino origin made up 1.0% of the population. In terms of ancestry, 66.8% were German, 19.3% were Norwegian, 7.6% were Russian, 6.3% were English, and 4.4% were American.

Of the 756 households, 25.0% had children under the age of 18 living with them, 65.5% were married couples living together, 4.8% had a female householder with no husband present, 26.7% were non-families, and 22.6% of all households were made up of individuals. The average household size was 2.44 and the average family size was 2.84. The median age was 47.6 years.

The median income for a household in the county was $62,308 and the median income for a family was $75,069. Males had a median income of $60,592 versus $28,409 for females. The per capita income for the county was $29,348. About 6.5% of families and 9.7% of the population were below the poverty line, including 13.0% of those under age 18 and 19.6% of those age 65 or over.

Population by decade

City

• Center (county seat)

Unincorporated communities^[5]