It is named for Haakon VII, who became king of Norway in 1905, in order to attract Norwegian settlers to the county.

[5] Most of South Dakota's counties are named for early South Dakota officials or legislators, or for physical features (Fall River and Lake), or are derived from Native American words (Minnehaha and Yankton), or from counties in other states (Jones and Walworth), with one (Aurora) named for a Roman goddess, one for an animal (Buffalo), and one (Union) for a concept.

The terrain of Haakon County consists of semi-arid rolling hills, carved with gullies and drainages, partially devoted to agriculture.

[6] The terrain slopes to the northeast, and its highest point is near the midpoint of its western boundary line, at 2,802 ft (854 m) ASL.

In terms of ancestry, 45.4% were German, 19.4% were Irish, 17.6% were Norwegian, 8.6% were English, 6.2% were Czech, 5.1% were Dutch, and 1.2% were American.

In 2007, the average price (in US dollars) for housing was:[16] Source:[6] The Haakon County voters are reliably Republican.