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Illinois Description


Retreating Ice Age glaciers certainly left their mark on large areas of Illinois, giving way to a landscape of rolling hills and prairies, thus earning Illinois the nickname, "The Prairie State."

An advanced mound-building culture (called the Mississippians) flourished in this area of North America from 800 A.D., up to the mid-15th century. That civilization vanished for unknown reasons.

jacques marquetteIn the early 16th century (the Illiniwek Confederation) a political alliance of local Native American Indian tribes was formed. The name Illiniwek later gave Illinois its name. Eventually, the Pottawatomie, Miami, and Sauk Indians also inhabited the area.

In 1673 French explorers Jacques Marquette and Louis Joliet began their exploration of the Illinois and Mississippi Rivers. Others followed, and for much-needed protection from indigenous Indians, forts were built.

The French claimed all of this new land for their home country, and it became part of a vast slice of land across North America called New France.

It remained a part of the French Empire until the Treaty of Paris of 1763 when it passed to the victorious British in the French and Indian War (1754-1763).

During the American Revolutionary War (1775-1783), an estimated 2000 Native American hunters inhabited the area. In 1778, George Rogers Clark, a military officer from the Virginia Colony, led American forces into Illinois to fight the British and to claim the land.

indiana territoryAfter the war, in 1783, this entire region was ceded to the United States by the State of Virginia, and it became part of the Northwest Territory; land that would be settled, and eventually divided into individual states within the United States.

From the previously established Indiana Territory, the Illinois Territory was created on March 1, 1809, by an Act of U.S. Congress. By 1810, settlers poured into the area, many arriving via river barges that traveled down the Ohio River. Subsequently, the southern part of the state developed first.

Illinois became the 21st U.S. State in 1818 with its capital in Kaskaskia. In 1819 the capital was moved to Vandalia, and later to Springfield.

The Black Hawk War of 1832 resulted in all of the remaining native American tribes being driven west of the Mississippi River. The expansion of railroads in the 19th century facilitated the arrival of a large number of immigrant farmers from Sweden and Germany.

Illinois Cities, Counties & Area Codes

City County Area Code
Quincy Adams 217
Cairo Alexander 618
Greenville Bond 618
Belvidere Boone 815
Mount Sterling Brown 217
Princeton Bureau 815
Hardin Calhoun 618
Savanna Carroll 815
Beardstown Cass 217
Champaign Champaign 217
Taylorville Christian 217
Marshall Clark 217
Flora Clay 618
Carlyle Clinton 618
Charleston Coles 217
Chicago Cook 847 , 312
Robinson Crawford 618
Neoga Cumberland 217
DeKalb DeKalb 815
Clinton Dewitt 217
Tuscola Douglas 217
Naperville DuPage 630
Paris Edgar 217
Albion Edwards 618
Effingham Effingham 217
Vandalia Fayette 618
Paxton Ford 217
West Frankfort Franklin 618
Canton Fulton 309
Shawneetown Gallatin 618
Carrollton Greene 217
Morris Grundy 815
McLeansboro Hamilton 618
Carthage Hancock 217
Elizabethtown Hardin 618
Oquawka Henderson 309
Kewanee Henry 309
Watseka Iroquois 815
Carbondale Jackson 618
Newton Jasper 618
Mount Vernon Jefferson 618
Jerseyville Jersey 618
Galena Jo Daviess 815
Vienna Johnson 618
Elgin Kane 847
Aurora Kane 630
Kankakee Kankakee 815
Oswego Kendall 630
Galesburg Knox 309
Ottawa La Salle 815
Waukegan Lake 847
Lawrenceville Lawrence 618
Dixon Lee 815
Pontiac Livingston 815
Lincoln Logan 217
Decatur Macon 217
Carlinville Macoupin 217
Granite City Madison 618
Centralia Marion 618
Henry Marshall 309
Havana Mason 309
Metropolis Massac 618
Macomb McDonough 309
Crystal Lake McHenry 815
Bloomington McLean 309
Petersburg Menard 217
Aledo Mercer 309
Waterloo Monroe 618
Litchfield Montgomery 217
Jacksonville Morgan 217
Sullivan Moultrie 217
Rochelle Ogle 815
Peoria Peoria 309
Du Quoin Perry 618
Monticello Piatt 217
Pittsfield Pike 217
Golconda Pope 618
Mounds Pulaski 618
Granville Putnam 815
Chester Randolph 618
Olney Richland 618
Moline Rock Island 309
Belleville Saint Clair 618
Harrisburg Saline 618
Springfield Sangamon 217
Rushville Schuyler 217
Winchester Scott 217
Shelbyville Shelby 217
Wyoming Stark 309
Freeport Stephenson 815
Pekin Tazewell 309
Anna Union 618
Danville Vermilion 217
Mount Carmel Wabash 618
Monmouth Warren 309
Nashville Washington 618
Fairfield Wayne 618
Carmi White 618
Sterling Whiteside 815
Joliet Will 708
Marion Williamson 618
Rockford Winnebago 815
Metamora Woodford 309

About the Author

John Moen is a cartographer who along with his wife are the orignal founders of worldatlas.com. He and his wife, Chris Woolwine-Moen, produced thousands of award-winning maps that are used all over the world and content that aids students, teachers, travelers and parents with their geography and map questions. Today, it's one of the most popular educational sites on the web.

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This page was last updated on April 7, 2017.