The Illinois Valley which is the region through which a large area of the Illinois Michigan Canal traverses has a long history.   During the era of the glaciers, the Illinois Valley was the large drainage site for the Great Lakes to the Mississippi River.  This phenomenon occurred over multiple eras.   The indigenous native population inhabited this site for thousands of years.  There were a series of multiple tribes in this region.   These native populations were predominately hunters.   They were familiar with the geography of the area and the waterways.   They were familiar with the courses of the Mississippi River, the Illinois River, and the Des Plaines River in their course towards Lake Michigan.  This waterway was not complete and required a portage between the Des Plaines River and the Chicago River.