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Related to Illinois: University of Illinois


, indigenous people of North America
Illinois (ĭlˌənoiˈ, –noizˈ), confederation of Native North Americans, comprising the Cahokia, the Kaskaskia, the Michigamea, the Moingwena, the Peoria, and the Tamaroa tribes. They belong to the Algonquian branch of the Algonquian-Wakashan linguistic stock (see Native American languages). In the mid-17th cent. they lived in S Wisconsin, N Illinois, and sections of Iowa and Missouri. They then numbered some 6,500. Jacques Marquette and Louis Jolliet are believed to have been the first Europeans to travel (1673) through Illinois territory. Father Claude Jean Allouez, a Jesuit missionary, visited them in 1676 and stayed with them for years. By 1750 wars with the Sioux, the Fox, and the Iroquois had reduced the population to some 2,000. In 1769 the assassination of the celebrated Ottawa chief Pontiac by a Kaskaskia provoked the Lake tribes (the Ojibwa, the Ottawa, the Potawatami, the Kickapoo, and the Sac and Fox) to vengeance. They began a war of extermination, which in a few years diminished the Illinois to a small number, who sought asylum at the French settlement at Kaskaskia. By 1800 there remained some 150 Illinois. In 1833 the survivors, represented by the Kaskaskia and the Peoria, sold their lands in Illinois and moved W of the Mississippi. Their descendants now occupy tribal land in NE Oklahoma, which they share with the Wea and Piankashaw. The Peoria's relationship with the federal government was terminated in 1959. In 1990 there were about 1,300 Peoria in the United States.


, state, United States

Illinois, midwestern state in the N central United States. It is bordered by Lake Michigan and Indiana (E); Kentucky, across the Ohio River (SE); Missouri and Iowa, across the Mississippi River (W); and Wisconsin (N).

Facts and Figures

Area, 56,400 sq mi (146,076 sq km). Pop. (2020) 12,671,821, a 1.2% decrease since the 2010 census. As of the 2020 census, the state's population was: White alone, 76.8%; Black alone, 14.6%; Hispanic or Latino, 17.5%; American Indian and Alaska native alone, 0.6%; Asian alone, 5.9%; Two or More Races, 2.1%. Capital, Springfield. Largest city, Chicago. Statehood, Dec. 3, 1818 (21st state). Highest pt., Charles Mound, 1,235 ft (377 m); lowest pt., Mississippi River, 279 ft (85 m). Nicknames, Inland Empire; Prairie State. Motto, State Sovereignty—National Union. State bird, cardinal. State flower, native violet. State tree, white oak. Abbr., Ill.; IL


The broad level lands that gave Illinois the nickname Prairie State were fashioned by late Cenozoic glaciation, which leveled rugged ridges and filled valleys over the northern and central parts of the state. The fertile prairies are drained by more than 275 rivers, most of which flow to the Mississippi-Ohio system; the Illinois is the largest river in the state.

These rivers provided early explorers a way SW from Lake Michigan into the interior of the continent and later, in the days of canal building, played a big part in hastening settlement of the prairies. The completion of the Erie Canal linked Illinois, through the Great Lakes, to the eastern seaboard of the United States. The Illinois Waterway links Chicago to the Mississippi basin as the old Chicago and Illinois and Michigan canals once did, and the St. Lawrence Seaway provides access for oceangoing vessels. The waterways are but a part of a transportation complex that includes railroads, airlines (Chicago's O'Hare airport is one of the busiest in the world), and an extensive modern highway system.

The state's climate is continental, with extreme seasonal variations of temperature in parts of the state. Among Illinois's many tourist attractions are Shawnee National Forest, with recreational facilities; the Cahokia Mounds; and many state parks and historical sites, including New Salem and Lincoln's home and burial place in Springfield. An additional summer attraction is the Illinois State Fair. Springfield is the capital; Chicago, Rockford, and Peoria are the largest cities.


Rich land, adequate rainfall (32–36 in./81–91 cm annually), and a long growing season make Illinois an important agricultural state. It consistently ranks among the top states in the production of corn and soybeans. Hogs and cattle are also principal sources of farm income. Other major crops include hay, wheat, and sorghum. Beneath the fertile topsoil lies mineral wealth, including fluorspar, bituminous coal, and oil; Illinois ranks high among the states in the production of coal, and its reserves are greater than any other state east of the Rocky Mts. Its agricultural and mineral resources, along with its excellent lines of communication and transportation, made Illinois industrial; by 1880 income from industry was almost double that from agriculture.

Leading Illinois manufactures include electrical and nonelectrical machinery, food products, fabricated and primary metal products, and chemicals; printed and published materials are also important. Metropolitan Chicago, the country's leading rail center, is also a major industrial, as well as a commercial and financial, center. Suburbs of Chicago such as Schaumburg and Oak Brook have become important business centers. Scattered across the northern half of the state are cities with specialized industries—Elgin, Peoria, Rock Island, Moline, and Rockford. Industrially important cities in central Illinois include Springfield and Decatur.

Government, Politics, and Higher Education

The governor of Illinois is elected for a term of four years. The state legislature, called the general assembly, consists of a senate with 59 members and a house of representatives with 118 members. Illinois elects 18 representatives and 2 senators to the U.S. Congress and has 20 electoral votes. The state is considered a Democratic stronghold along with New York and California.

Institutions of higher learning in Illinois include the Univ. of Illinois, at Urbana-Champaign and Chicago; DePaul Univ., the Univ. of Chicago, and the Illinois Institute of Technology, at Chicago; Northwestern Univ., at Evanston; Illinois State Univ., at Normal; and Southern Illinois Univ., at Carbondale and Edwardsville.


Early Inhabitants and European Exploration

At the end of the 18th cent. the Illinois, Sac, Fox, and other Native American groups were living in the river forests, where many centuries before them the prehistoric Mound Builders had dwelt. French explorers and missionaries came to the region early. Father Marquette and Louis Jolliet, on their return from a trip down the Mississippi, paddled up the Illinois River in 1673, and two years later Marquette returned to establish a mission in the Illinois country.

In 1679 the French explorer Robert Cavelier, sieur de La Salle, went from Lake Michigan to the Illinois, where he founded (1680) Fort Creve Coeur and with his lieutenant, Henri de Tonti, completed (1682–83) Fort St. Louis on Starved Rock cliff. French occupation of the area was sparse, but the settlements of Cahokia and Kaskaskia achieved a minor importance in the 18th cent., and the area was valued for fur trading.

By the Treaty of Paris of 1763, ending the French and Indian Wars, France ceded all of the Illinois country to Great Britain. However, the British did not take possession until resistance, led by the Ottawa chief, Pontiac, was quelled (1766). In the American Revolution, George Rogers Clark and his expedition captured (1778) the British posts of Cahokia and Kaskaskia before going on to take Vincennes. The Illinois region was an integral part of the Old Northwest that came within U.S. boundaries by the 1783 Treaty of Paris ending the American Revolution. Under the Ordinance of 1787 the area became the Northwest Territory. Made part of Indiana Territory in 1800, Illinois became a separate territory in 1809.

Statehood and Settlement

The fur trade was still flourishing throughout most of Illinois when it became a state in 1818, but already settlers were pouring down the Ohio River by flatboat and barge and across the Genesee wagon road. In 1820 the capital was moved from Kaskaskia to Vandalia. The Black Hawk War (1832) practically ended the tenure of the Native Americans in Illinois and drove them W of the Mississippi. In the 1830s there was heavy and uncontrolled land speculation. Mob fury broke out with the murder (1837) of the abolitionist Elijah P. Lovejoy at Alton and in the lynching (1844) of the Mormon leader Joseph Smith and his brother Hyrum at Carthage.

Industrialization and Abraham Lincoln

Industrial development came with the opening of an agricultural implements factory by Cyrus H. McCormick at Chicago in 1847 and the building of the railroads in the 1850s. During this period the career of Abraham Lincoln began. In the state legislature, Lincoln and his colleagues from Sangamon co. had worked hard and successfully to bring the capital to Springfield in 1839. As Illinois moved toward a wider role in the country's affairs, Lincoln and another Illinois lawyer, Stephen A. Douglas, won national attention with their debates on the slavery issue in the senatorial race of 1858. In 1861, Lincoln became president and fought to preserve the Union in the face of the South's secession. During the Civil War, Illinois supported the Union, but there was much proslavery sentiment in the southern part of the state.

By the 1860s industry was well established, and many immigrants from Europe had already settled in the state, foreshadowing the influx still to come. Immediately after the Civil War, industry expanded to tremendous proportions, and the Illinois legislature, by setting aside acreage for stockyards, prepared the way for the development of the meatpacking industry. Economic development had outrun the construction of facilities, and Chicago was a mass of flimsy wooden structures when the fire of 1871 destroyed most of the city.

Discontent and the Rise of the Labor Movement

In the latter part of the 19th cent. farmers in the state revolted against exorbitant freight rates, tariff discrimination, and the high price of manufactured goods. Illinois farmers enthusiastically joined the Granger movement. Laborers in factories, railroads, and mines also became restive, and from 1870 to 1900 Illinois was the scene of such violent labor incidents as the Haymarket Square riot of 1886 and the Pullman strike of 1894.

In the 20th cent. labor conditions improved, but violent labor disputes persisted, notably the massacre at Herrin in 1922 during a coal-miners' strike and the bloody riot during a steel strike at Chicago in 1937. State politics became divided by the conflicting forces of farmers, laborers, and corporations, and opposing political machines came into being downstate and upstate.

Diversification and Change

In 1937 new oil fields were discovered in southern Illinois, further enhancing the state's industrial development. During World War II the nation's first controlled nuclear reaction was accomplished at the Univ. of Chicago, paving the way for development of nuclear weapons during the war. The war also spurred the further growth of the Chicago metropolitan area, and in the postwar period thousands of African Americans from the rural south came seeking industrial work.

Adlai E. Stevenson, governor of Illinois from 1949 to 1953, achieved national prominence in winning the Democratic presidential nomination in 1952 and 1956. Also during the 1950s the “gateway amendment” to the Illinois constitution simplified the state's constitutional amendment process. In 1970, Illinois adopted a new state constitution that, among other reforms, banned discrimination in employment and housing.

Southern Illinois experienced population declines in the 1950s and 60s as farms in the south became more mechanized, providing fewer jobs in the area. The area was hard-hit again in the 1980s as farm prices fell and farm machinery, the major industrial product of southern Illinois, was no longer in high demand. The northern portion of the state saw a major decline in manufacturing in the 1970s and 80s, which was partially offset by an increase in the service and trade industry and Chicago's continued strength as a financial center. The election of Ronald Reagan as president in 1980 was the first time someone born in the state had won that office, and Barack Obama, who became the first African-American to be elected president in 2008, had served as U.S. senator from Illinois before his election. Flooding along the Mississippi inundated large areas of W Illinois in 1993.

In 2002 a Democrat, Rod Blagojevich, was elected to the office; he was reelected in 2006. In 2009, however, he was impeached and removed from office because of accusations that he had sought to gain from his appointment of the U.S. senator who would succeed Obama. (In 2011 he was convicted in federal courts on charges arising from the case.) Lt. Gov. Patrick J. Quinn, also a Democrat, replaced Blagojevich and won election to the office in 2010, but Quinn lost to Republican Bruce Rauner in 2014. In 2018, Democrat J. B. Pritzker was elected governor; he has championed liberal issues including legalizing the use of recreational marijuana and expanding Medicaid coverage. He also was a strong advocate to replace the state's flat income tax with a graduated one, however a Nov. 2020 ballot referendum to make that change failed to pass.


See W. L. Burton, The Trembling Land: Illinois in the Age of Exploration (1966); V. Hicken, Illinois in the Civil War (1966); R. J. Jensen, Illinois: A History (1978); R. E. Nelson, ed., Illinois (1978); C. W. Horrell et al., Land Between the Rivers (1982); A. D. Horsley, Illinois: A Geography (1986); P. F. Nardulli, Diversity, Conflict, and State Politics (1989).


, river, United States
Illinois, river, 273 mi (439 km) long, formed by the confluence of the Des Plaines and Kankakee rivers, NE Ill., and flowing SW to the Mississippi at Grafton, Ill. It is an important commercial and recreational waterway. The Illinois forms the greater part of the Illinois Waterway, which links the Great Lakes with the Mississippi. The chief city on the river is Peoria.
The Columbia Electronic Encyclopedia™ Copyright © 2022, Columbia University Press. Licensed from Columbia University Press. All rights reserved.

Illinois State Information

Phone: (217) 782-2000

Area (sq mi):: 57914.38 (land 55583.58; water 2330.79) Population per square mile: 229.60
Population 2005: 12,763,371 State rank: 0 Population change: 2000-20005 2.80%; 1990-2000 8.60% Population 2000: 12,419,293 (White 67.80%; Black or African American 15.10%; Hispanic or Latino 12.30%; Asian 3.40%; Other 7.90%). Foreign born: 12.30%. Median age: 34.70
Income 2000: per capita $23,104; median household $46,590; Population below poverty level: 10.70% Personal per capita income (2000-2003): $32,185-$32,965
Unemployment (2004): 6.20% Unemployment change (from 2000): 1.70% Median travel time to work: 28.00 minutes Working outside county of residence: 25.20%

List of Illinois counties:

  • Adams County
  • Alexander County
  • Bond County
  • Boone County
  • Brown County
  • Bureau County
  • Calhoun County
  • Carroll County
  • Cass County
  • Champaign County
  • Christian County
  • Clark County
  • Clay County
  • Clinton County
  • Coles County
  • Cook County
  • Crawford County
  • Cumberland County
  • De Witt County
  • DeKalb County
  • Douglas County
  • DuPage County
  • Edgar County
  • Edwards County
  • Effingham County
  • Fayette County
  • Ford County
  • Franklin County
  • Fulton County
  • Gallatin County
  • Greene County
  • Grundy County
  • Hamilton County
  • Hancock County
  • Hardin County
  • Henderson County
  • Henry County
  • Iroquois County
  • Jackson County
  • Jasper County
  • Jefferson County
  • Jersey County
  • Jo Daviess County
  • Johnson County
  • Kane County
  • Kankakee County
  • Kendall County
  • Knox County
  • Lake County
  • LaSalle County
  • Lawrence County
  • Lee County
  • Livingston County
  • Logan County
  • Macon County
  • Macoupin County
  • Madison County
  • Marion County
  • Marshall County
  • Mason County
  • Massac County
  • McDonough County
  • McHenry County
  • McLean County
  • Menard County
  • Mercer County
  • Monroe County
  • Montgomery County
  • Morgan County
  • Moultrie County
  • Ogle County
  • Peoria County
  • Perry County
  • Piatt County
  • Pike County
  • Pope County
  • Pulaski County
  • Putnam County
  • Randolph County
  • Richland County
  • Rock Island County
  • Saint Clair County
  • Saline County
  • Sangamon County
  • Schuyler County
  • Scott County
  • Shelby County
  • Stark County
  • Stephenson County
  • Tazewell County
  • Union County
  • Vermilion County
  • Wabash County
  • Warren County
  • Washington County
  • Wayne County
  • White County
  • Whiteside County
  • Will County
  • Williamson County
  • Winnebago County
  • Woodford County
  • Counties USA: A Directory of United States Counties, 3rd Edition. © 2006 by Omnigraphics, Inc.

    Illinois Parks

    Parks Directory of the United States, 5th Edition. © 2007 by Omnigraphics, Inc.
    The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



    a state in the northern United States. It is located in the northern part of the Central Plain, between Lake Michigan, the Ohio River, and the Mississippi River. Area, 146,000 sq km. Population, 11.1 million (1970; 83 percent is urban). Capital, Springfield. The most important city and chief economic center is Chicago; more than 60 percent of the state’s population lives in Chicago and its suburbs.

    Illinois is located on major transcontinental routes and the most important internal waterways of the United States. The topography is a rolling plain (with heights up to 378 m in the north), covered with rich black soil. The climate is temperate and continental. During the coldest month the mean temperature is— 3°C, and during the warmest month, 25°C. The annual precipitation ranges from 800 to 1,000 mm. Illinois is rich in coal, petroleum, fluorspar, and other minerals.

    Illinois is a highly developed industrial and agricultural state, ranking fifth in the United States in industrial and agricultural production and in population. Of the economically active population, 32 percent are employed in manufacturing, 0.5 percent in mining, and 4 percent in agriculture. In 1968, the state’s mineral output included 56 million tons of coal and 10.6 million tons of petroleum. Of the 1.4 million workers employed in the manufacturing industry (1969; 980,000 in Chicago), nearly 50 percent are employed in the machine-building and metal-working industries, almost 10 percent in metallurgy, and 10 percent in the food industry. The leading branches of industry include radioelec-tronics; locomotive and railroad-car building (Chicago, Rock-ford, Rock Island, and Peoria); ferrous metallurgy (primarily in Chicago); petroleum-refining; chemicals; meat packing (Chicago and East St. Louis); and the production of electrical, industrial, and construction equipment, as well as of agricultural implements. The printing, garment, and distilling industries are well developed.

    Illinois is part of the Corn Belt, the most important agricultural region in the United States. Eighty-five percent of the land is under cultivation. The principal crops are corn (second in production in the USA) and soybeans (first in production); wheat, oats, and forage are also grown. Livestock-raising constitutes more than 50 percent of agricultural production. As of January 1970 livestock in Illinois included 3.3 million cattle, 6.6 million hogs, and 389,000 sheep. There are 18,000 km of railroad lines and 170,000 km of highways in Illinois. The Illinois Waterway, a canal route connecting the Great Lakes system with the Mississippi River Basin, passes through the state.




    a river in the United States, left tributary of the Mississippi River. It is formed by the junction of the Des Plaines and Kankakee rivers. Length, 437 km (from its source at the Kankakee, 653 km); basin area, 82,000 sq km. The riverbed has a number of enlargements resembling lakes. It is fed by rain and snow. There are high waters between March and May. The water is at its lowest level during the summer and fall. The average annual discharge is approximately 1,000 cu m per sec. In its upper course the Illinois is linked by navigable canals with Lake Michigan (at Chicago) and with the Mississippi River. The river has locks and is navigable along its entire course. Above the city of La Salle, it is paralleled by a canal. The city of Peoria is located on the Illinois River. [10-374 -2]

    The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


    Twenty-first state; admitted on December 3, 1818

    The 150th, or sesquicentennial, anniversary of Illinois’ state­hood was celebrated throughout the state during 1968. In December 1967, a year-long exhibit on Illinois history opened at Chicago’s Field Museum of Natural History. Miniature replicas of historic rooms—Carl Sandburg’s birthplace, Jane Addams’s Hull House office, and the Palmer House Hotel’s Silver Dollar Barber Shop of 1875—were on display in Carson Pirie Scott department stores. Lincoln’s birthday on February 12 was observed with programs commemorating his career in Illinois. On July 4, there was a parade, drama, musical events, fireworks, and speeches at Steeleville. As part of the year-long celebration, the Old State House in Springfield was restored.

    State capital: Springfield
    Nicknames: Prairie State; Land of Lincoln; Corn State
    State motto: State Sovereignty, National Union
    State animal: White-tailed deer (Odocoileus virginianus)
    State amphibian: Eastern tiger salamander
    State bird: Cardinal (Cardinalis cardinalis)
    State dance: Square dance
    State fish: Bluegill (Lepomis macrochirus)
    State flower: Violet (Viola)
    State fossil: Tully Monster (Tullimonstrum gregarium)
    State insect: Monarch butterfly (Danaus plexippus)
    State mineral: Fluorite
    State prairie grass: Big bluestem (Andropogon furcatus)
    State reptile: Painted turtle
    State song: “Illinois”
    State tree: White oak (Quercus alba)

    More about state symbols at:

    More about the state at:


    AmerBkDays-2000, p. 809 AnnivHol-2000, p. 201


    State web site:

    Office of the Governor State Capitol Bldg Rm 207 Springfield, IL 62706 217-782-6830 fax: 217-782-1853

    Secretary of State State Capitol Bldg Rm 213 Springfield, IL 62756 217-782-2201 fax: 217-785-0358

    Illinois State Library 300 S 2nd St Springfield, IL 62701 217-782-2994 fax: 217-785-4326

    Legal Holidays:

    Christmas EveDec 24
    Day after ThanksgivingNov 25, 2011; Nov 23, 2012; Nov 29, 2013; Nov 28, 2014; Nov 27, 2015; Nov 25, 2016; Nov 24, 2017; Nov 23, 2018; Nov 29, 2019; Nov 27, 2020; Nov 26, 2021; Nov 25, 2022; Nov 24, 2023
    Lincoln's BirthdayFeb 12
    Washington's BirthdayFeb 21, 2011; Feb 20, 2012; Feb 18, 2013; Feb 17, 2014; Feb 16, 2015; Feb 15, 2016; Feb 20, 2017; Feb 19, 2018; Feb 18, 2019; Feb 17, 2020; Feb 15, 2021; Feb 21, 2022; Feb 20, 2023
    Holidays, Festivals, and Celebrations of the World Dictionary, Fourth Edition. © 2010 by Omnigraphics, Inc.


    1. a state of the N central US, in the Midwest: consists of level prairie crossed by the Illinois and Kaskaskia Rivers; mainly agricultural. Capital: Springfield. Pop.: 12 653 544 (2003 est.). Area: 144 858 sq. km (55 930 sq. miles)
    2. a river in Illinois, flowing SW to the Mississippi. Length: 439 km (273 miles)
    Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
    References in periodicals archive ?
    More information on the Illinois Insurance Pre-Licensing Program can be found at
    The cost to purchase a random number Cardinals plate for a currently titled vehicle with valid Illinois registration will be $69.
    * Maria Rodriguez, RE/MAX Partners, Berwyn, Ill., 116th in U.S., 12th in Illinois.
    Once the work plan has been approved by the Illinois EPA and the Jackson County Health Department, the landfill will be able to dispose of the currently contained, solidified liquid waste.
    Cory Foster, senior policy advisor, Illinois Department of Corrections, Chicago
    Data service provider US Signal said today that it is undertaking a significant expansion of its long-haul fibre network in Southern and Central Illinois, St.
    The act also permits wineries anywhere that produce under 25,000 gallons per year to self-distribute up to 5,000 gallons annually direct to Illinois retailers, providing they have a Wine Shipper's License, according to Katie Ridgway, communications manager of the Illinois Department of Revenue.
    The Illinois Division of Professional Regulation filed an emergency rule Sept.
    "[Poorer] areas end up trying to squeeze blood out of a turnip," said Bindu Batchu, campaign manager for A+ Illinois, a coalition of groups working to boost school funding and improve the quality of education in the state.

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