The current courthouse was built in 1892 after the county had outgrown the previous one.

[5] Iowa County is home to the Amana Colonies, a group of settlements of German Pietists, comprising seven villages.

Calling themselves the Ebenezer Society or the Community of True Inspiration (German: die Gemeinde der wahren Inspiration), they first settled in New York state near Buffalo in what is now West Seneca.

Today, Amana is a major tourist attraction known mainly for its restaurants and craft shops, and the colonies as a whole have been listed as a National Historic Landmark since 1965.

[14] As of the census[15] of 2000, there were 15,671 people, 6,163 households, and 4,301 families residing in the county.

25.90% of all households were made up of individuals, and 12.50% had someone living alone who was 65 years of age or older.

In the 2008 US presidential election, a nearly equal number of Iowa County voters voted for each major candidate, with Barack Obama winning the county by a narrow margin of 14 votes.

[16] In the 2012 US presidential election, Mitt Romney received 4,551 votes (51.8%).

The population ranking of the following table is based on the 2020 census of Iowa County.