Frankfort is a village in Will and Cook Counties, Illinois, United States. The population was 17,782 at the 2010 census. According to Forbes.com, in 2007 the village ranked as the 36th fastest growing suburb in the United States.
There is no basis in fact that the Village of Frankfort's name was changed from Frankfurt during World War 1 because the citizens were ashamed of the name "Frankfurt" because it seemed as if we were supporting Germany. Any documents using the spelling "Frankfurt" before 1917 are in error. The maps of Will County, drawn as early as 1853, show the name is correctly spelled Frankfort. The name Frankfort was taken from the Frankfort Township name as designated by the governing board of Will County It was commonly known as "Frankfort Station" after the opening of the Joliet & Northern Indiana Railroad through the township in 1855. In fact the official plat of the community dated March 1855 shows the name as Frankfort. Property deed abstracts and railroad documents also show that the name was always Frankfort. Local residents incorporated Frankfort as a village, with the village form of local government in 1879.
First inhabited by Native Americans, including the Potawatomi and Sac and Fox tribes, Frankfort was used as a conduit between the Des Plaines and St. Joseph Rivers. Originally, the area was part of the Virginia Territory before the French signed a treaty with Manitoqua, the Potawatomi Chief, for land in the Prestwick area. The first pioneers came to Frankfort in the early 1830s by means of the Des Plaines River from the southwest and by wagon from the east along the Sauk Trail, a roadway that still exists today.