Frankfort is a city in Clinton County, Indiana, United States.

[4] Brothers John, William and Nicholas Pence, previously of Warren County, Ohio, settled on the land on which Frankfort now stands in 1829, having entered it from the government in 1827 and 1828.

The new town was named Frankfort at the brothers' request and honors their German great-grandparents' home of Frankfurt am Main.

[5] The town of Frankfort was laid off on the 60-acre (240,000 m2) tract by William Douglass, the county agent, and the plat filed on June 8, 1830.

The original plat consisted of 64 lots in eight blocks surrounding a public square where the courthouse now stands.

The county board paid contractors Allen & Michael the sum of $20 to erect the first courthouse, a 1+1⁄2-story temporary structure made of logs hewn from trees that grew on the square and surrounding streets.

Indianapolis architect George W. Bunting in 1881 designed the third courthouse, a 165-foot (50 m) tall structure built of Indiana limestone by contractors Farman & Pearce for approximately $200,000.

[6] The youngest elected mayor of Frankfort was Robert Keene at the age of 21 when he took office in January 1922 just one month prior to the fire at Old Stoney on February 24, 1922.

[7] According to the 2010 census, Frankfort has a total area of 6.31 square miles (16.34 km2), all land.

[12] Successor railroads such as CSX and Norfolk Southern have the tracks or right of ways of the routes today.