[2] Franklin County is part of the Cincinnati, OH–KY–IN Metropolitan Statistical Area.

Its low rolling hills, once completely wooded, have been partially cleared and leveled for agricultural use.

[3] The highest point in the county (1,070 feet/330 meters ASL) is a small hill 1.0 mile (1.6 km) north of Andersonville.

[5] The future state of Indiana was first regulated by congressional passage of the Northwest Ordinance in 1787.

[6][7] Some early settlers of Franklin County were Primitive Baptists who came with Elder William Tyner from Virginia in 1797, after the American Revolutionary War.

In the 1830s modernism reached the county, bringing innovations such as Sunday schools, Missionary Societies, and the playing of organs.

Organs were particularly anathema to the Primitive Party, who considered it akin to Aaron's golden calf.

The Big Cedar congregation divided into two over these issues, but the two groups arrived at an amicable settlement.

[9] Governors James B. Ray, Noah Noble and David Wallace were known as the "Brookville Triumvirate."

[10] James B. Goudie Jr. (1769–1836), Speaker of the Indiana House, was also from Franklin County.

The commissioners execute acts legislated by the council, collect revenue, and manage county government.

[15] As of the 2010 United States Census, there were 23,087 people, 8,579 households, and 6,447 families in the county.