The following year a portion of Putnam was removed to form Dodge County.

[4] In its early years, the county seat changed frequently, often with contentious debate.

Putnamville, Bryant Station (both no longer in existence), and Hartford all served until a central location called Harmony, later renamed Unionville, was chosen.

[5] In the 1860 U.S. Census Putnam County had 9,240 residents, with eighteen sawmills and three flour mills.

Following the arrival of the Burlington & Southwestern Railway in 1873, coal mining became a major industry, especially in the east of the county.

[7] Putnam County lost over two-thirds of its population between the years 1900 and 2000 (see census data below), when the United States changed from a rural to an urban country.

The Republican Party predominantly controls politics at the local level in Putnam County.