[9] The building stood across from what later would become the James McCollister Farmstead on land later owned by Philip Clark.

[9] This location was in the southeast corner of the intersection of Harrison and Clinton Streets.

[12] The building was apparently built of brick with stone and wood ornamentation.

[14] It was bid at a cost of $111,000 and built by the firm Rowson & Son of Johnson County.

[16] The building's tower was based on Henry Hobson Richardson's design for the spire of Trinity Church in Boston.

[18] The currently unused jail that stands to the west of the courthouse was designed by C.L.

Wundt of Burlington, Iowa on behalf of the Stewart Iron Works in Cleveland and bid for $14,000.

30.20% of all households were made up of individuals, and 5.60% had someone living alone who was 65 years of age or older.

This trend predates the recent swing toward the Democrats in counties influenced by college towns.

[30] In 2024, it was the only county to not vote for Donald Trump in the state's Republican presidential caucuses.

[31][32][33] Johnson County's Democratic bent is just as pronounced at the state level.

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