Illinois is a state in the midwestern region of the United States. It is the 5th most populous state and 25th largest state in terms of land area, and is often noted as a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal, timber, and petroleum in the south, Illinois has a diverse economic base and is a major transportation hub. The Port of Chicago connects the state to other global ports from the Great Lakes, via the Saint Lawrence Seaway, to the Atlantic Ocean, as well as the Great Lakes to the Mississippi River, via the Illinois River. For decades, O’Hare International Airport has been ranked as one of the world’s busiest airports. Illinois has long had a reputation as a bellwether both in social and cultural terms and politics.
Although today the state’s largest population center is around Chicago in the northern part of the state, the state’s European population grew first in the west, with French Canadian colonists who settled along the Mississippi River in the 17th and 18th century, and gave the area the name, Illinois Country. After the American Revolutionary War established the United States, American settlers began arriving crossing the Appalachians barrier range in the 1810s via the gaps of the Allegheny to boat building centers in Pittsburgh, from Cumberland, Maryland via the Cumberland Narrows pass to outfit in Brownsville, Pennsylvania, from North Carolina and Virginia via the Cumberland Gap to Kentucky and Tennessee, all on the Ohio River.
Source : https://en.wikipedia.org/wiki/Illinois