 Its county seat is Hallock.Evidence of occupation dating back 1800 years has been confirmed through archaeological expeditions done in the 1930s and 1970s around the burial mounds on the sand ridges in the eastern part of the county, which date to the Woodland Period.Evidence has been found that the Laurel, Arvilla, St. Croix, and Blackduck complexes were the area's early occupants.