[10] As of the 2010 census, there were 718 people, 335 households, and 219 families residing in the county.There were 422 housing units at an average density of 0.4 per square mile (0.15/km2).In terms of ancestry, 40.2% were American, 22.4% were German, 9.9% were English, 9.9% were Irish, and 7.4% were Norwegian.Treasure County voters are reliably Republican.They have only selected the Democratic Party candidate in five national elections (as of 2021) during the century of the county's existence as an independent unit.