[4] The Blanchard River, which passes through the county, was a key transportation route for early European-American settlers.

[5] As of the census[10] of 2000, there were 34,726 people, 12,200 households, and 9,308 families living in the county.

There were 12,753 housing units at an average density of 26 per square mile (10/km2).

21.30% of all households were made up of individuals, and 10.50% had someone living alone who was 65 years of age or older.

As of the 2010 United States Census, there were 34,499 people, 12,872 households, and 9,556 families living in the county.

There were 13,731 housing units at an average density of 28.5 per square mile (11.0/km2).

[11] In terms of ancestry, 65.6% identified as German, 7.8% were Irish, 7.3% were American, 4.7% were English, 2.4% were French, 1.8% were Swiss, 1.7% were Dutch, 1.6% were Italian, 1.4% were Scottish, 1.0% were Welsh, 0.8% were Hungarian and 0.8% were Polish.

The only 2 Democrats to win the county since then are Harry S. Truman in 1948 and Lyndon B. Johnson in 1964.

[15] The Putnam County Board of Education operates nine separate school districts county-wide.