[1][4] Brown County is part of the Aberdeen, SD Micropolitan Statistical Area.

Brown County lies on the north side of South Dakota.

[7] As of the 2020 census, there were 38,301 people, 16,130 households, and 9,595 families residing in the county.

Brown County was long a Democratic stronghold, home to notable Democrats including South Dakota Governor Ralph Herseth, US Senate majority leader Tom Daschle and Congresswoman Stephanie Herseth Sandlin.

It generally voted Democratic except in Republican landslides (though often relatively narrowly margins) in presidential elections from 1932 until 1996.