Illinois Information (Geography)
Land of Lincoln, Prairie State
State Sovereignty, National Union
|Anthem: " Illinois"|
Map of the United States with Illinois highlighted
|Before statehood||Illinois Territory|
|Admitted to the Union||December 3, 1818 (21st)|
|Largest metro||Chicago metropolitan area|
|• Governor||J. B. Pritzker ( D)|
|• Lieutenant Governor||Juliana Stratton (D)|
|Legislature||Illinois General Assembly|
|• Upper house||Senate|
|• Lower house||House of Representatives|
|Judiciary||Supreme Court of Illinois|
Dick Durbin (D)|
Tammy Duckworth (D)
|U.S. House delegation||13 Democrats|
5 Republicans ( list)
|• Total||57,915 sq mi (149,997 km2)|
|• Land||55,593 sq mi (143,969 km2)|
|• Water||2,320 sq mi (5,981 km2) 3.99%|
|• Length||390 mi (628 km)|
|• Width||210 mi (338 km)|
|Elevation||600 ft (180 m)|
|Highest elevation||1,235 ft (376.4 m)|
|Lowest elevation||280 ft (85 m)|
|• Total||12,671,821 |
|• Density||232/sq mi (89.4/km2)|
|• Density rank||12th|
|• Median household income||$65,030 |
|• Income rank||16th|
|• Official language||English |
|• Spoken language||English (80.8%)|
|Time zone||UTC−06:00 ( Central)|
|• Summer ( DST)||UTC−05:00 ( CDT)|
|ISO 3166 code||US-IL|
|Latitude||36° 58′ N to 42° 30′ N|
|Longitude||87° 30′ W to 91° 31′ W|
|Illinois state symbols|
|Amphibian||Eastern tiger salamander|
|Food||Gold Rush Apple, popcorn|
|Slogan||"Land of Lincoln"|
|Soil||Drummer silty clay loam|
|State route marker|
Released in 2003
|Lists of United States state symbols|
Illinois ( // ( listen) IL-ə-NOY) is a state in the Midwestern and Great Lakes regions of the United States. It has the fifth largest gross domestic product (GDP), the sixth largest population, and the 25th largest land area of all U.S. states. Illinois has been noted as a microcosm of the entire United States.  With Chicago in northeastern Illinois, small industrial cities and immense agricultural productivity in the north and center of the state, and natural resources such as 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 international ports via two main routes: from the Great Lakes, via the Saint Lawrence Seaway, to the Atlantic Ocean and from the Great Lakes to the Mississippi River, via the Illinois River, through the Illinois Waterway. The Mississippi River, the Ohio River, and the Wabash River form parts of the boundaries of Illinois. For decades, Chicago's 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, through the 1980s, in politics.
The capital of Illinois is Springfield, which is located in the central part of the state. Although today Illinois's largest population center is in its northeast, the state's European population grew first in the west as the French settled lands near the Mississippi River, when the region was known as Illinois Country and was part of New France. Following the American Revolutionary War, American settlers began arriving from Kentucky in the 1780s via the Ohio River, and the population grew from south to north. In 1818, Illinois achieved statehood. Following increased commercial activity in the Great Lakes after the construction of the Erie Canal, Chicago was incorporated in the 1830s on the banks of the Chicago River at one of the few natural harbors on the southern section of Lake Michigan.  John Deere's invention of the self-scouring steel plow turned Illinois's rich prairie into some of the world's most productive and valuable farmland, attracting immigrant farmers from Germany and Sweden. The Illinois and Michigan Canal (1848) made transportation between the Great Lakes and the Mississippi River valley faster and cheaper, and new railroads carried immigrants to new homes in the country's west and shipped commodity crops to the nation's east. The state became a transportation hub for the nation. 
By 1900, the growth of industrial jobs in the northern cities and coal mining in the central and southern areas attracted immigrants from Eastern and Southern Europe. Illinois was an important manufacturing center during both world wars. The Great Migration from the South established a large community of African Americans in the state, including Chicago, who founded the city's famous jazz and blues cultures.   Chicago, the center of the Chicago Metropolitan Area, is now recognized as a global city. Chicagoland, Chicago's metropolitan area, encompasses about 65% of the state's population. The most populous metropolitan areas outside the Chicago area include, Metro East (of Greater St. Louis), Peoria and Rockford.
Three U.S. presidents have been elected while living in Illinois: Abraham Lincoln, Ulysses S. Grant, and Barack Obama. Additionally, Ronald Reagan, whose political career was based in California, was born and raised in the state. Today, Illinois honors Lincoln with its official state slogan Land of Lincoln, which has been displayed on its license plates since 1954.   The state is the site of the Abraham Lincoln Presidential Library and Museum in Springfield and the future home of the Barack Obama Presidential Center in Chicago.
"Illinois" is the modern spelling for the early French Catholic missionaries and explorers' name for the Illinois Native Americans, a name that was spelled in many different ways in the early records. 
American scholars previously thought the name "Illinois" meant "man" or "men" in the Miami-Illinois language, with the original iliniwek transformed via French into Illinois.   This etymology is not supported by the Illinois language,[ citation needed] as the word for "man" is ireniwa, and plural of "man" is ireniwaki. The name Illiniwek has also been said to mean "tribe of superior men",  which is a false etymology. The name "Illinois" derives from the Miami-Illinois verb irenwe·wa—"he speaks the regular way". This was taken into the Ojibwe language, perhaps in the Ottawa dialect, and modified into ilinwe· (pluralized as ilinwe·k). The French borrowed these forms, changing the /we/ ending to spell it as -ois, a transliteration for its pronunciation in French of that time. The current spelling form, Illinois, began to appear in the early 1670s, when French colonists had settled in the western area. The Illinois's name for themselves, as attested in all three of the French missionary-period dictionaries of Illinois, was Inoka, of unknown meaning and unrelated to the other terms.  
During the early part of the Paleozoic Era, the area that would one day become Illinois was submerged beneath a shallow sea and located near the Equator. Diverse marine life lived at this time, including trilobites, brachiopods, and crinoids. Changing environmental conditions led to the formation of large coal swamps in the Carboniferous.
During the Pleistocene Epoch, vast ice sheets covered much of Illinois, with only the Driftless Area remaining exposed. These glaciers carved the basin of Lake Michigan and left behind traces of ancient glacial lakes and moraines. 
American Indians of successive cultures lived along the waterways of the Illinois area for thousands of years before the arrival of Europeans. The Koster Site has been excavated and demonstrates 7,000 years of continuous habitation. Cahokia, the largest regional chiefdom and Urban Center of the Pre-Columbian Mississippian culture, was located near present-day Collinsville, Illinois. They built an urban complex of more than 100 platform and burial mounds, a 50-acre (20 ha) plaza larger than 35 football fields,  and a woodhenge of sacred cedar, all in a planned design expressing the culture's cosmology. Monks Mound, the center of the site, is the largest Pre-Columbian structure north of the Valley of Mexico. It is 100 feet (30 m) high, 951 feet (290 m) long, 836 feet (255 m) wide, and covers 13.8 acres (5.6 ha).  It contains about 814,000 cubic yards (622,000 m3) of earth.  It was topped by a structure thought to have measured about 105 feet (32 m) in length and 48 feet (15 m) in width, covered an area 5,000 square feet (460 m2), and been as much as 50 feet (15 m) high, making its peak 150 feet (46 m) above the level of the plaza. The finely crafted ornaments and tools recovered by archaeologists at Cahokia include elaborate ceramics, finely sculptured stonework, carefully embossed and engraved copper and mica sheets, and one funeral blanket for an important chief fashioned from 20,000 shell beads. These artifacts indicate that Cahokia was truly an urban center, with clustered housing, markets, and specialists in toolmaking, hide dressing, potting, jewelry making, shell engraving, weaving and salt making.  The civilization vanished in the 15th century for unknown reasons, but historians and archeologists have speculated that the people depleted the area of resources. Many indigenous tribes engaged in constant warfare. According to Suzanne Austin Alchon, "At one site in the central Illinois River valley, one third of all adults died as a result of violent injuries."  The next major power in the region was the Illinois Confederation or Illini, a political alliance.  As the Illini declined during the Beaver Wars era, members of the Algonquian-speaking Potawatomi, Miami, Sauk, and other tribes including the Fox ( Mesquakie), Ioway, Kickapoo, Mascouten, Piankashaw, Shawnee, Wea, and Winnebago ( Ho-Chunk) came into the area from the east and north around the Great Lakes.  
European exploration and settlement prior to 1800
French explorers Jacques Marquette and Louis Jolliet explored the Illinois River in 1673. Marquette soon after founded a mission at the Grand Village of the Illinois in Illinois Country. In 1680, French explorers under René-Robert Cavelier, Sieur de La Salle and Henri de Tonti constructed a fort at the site of present-day Peoria, and in 1682, a fort atop Starved Rock in today's Starved Rock State Park. French Empire Canadiens came south to settle particularly along the Mississippi River, and Illinois was part of first New France, and then of La Louisiane until 1763, when it passed to the British with their defeat of France in the Seven Years' War. The small French settlements continued, although many French migrated west to Ste. Genevieve and St. Louis, Missouri, to evade British rule. 
A few British soldiers were posted in Illinois, but few British or American settlers moved there, as the Crown made it part of the territory reserved for Indians west of the Appalachians, and then part of the British Province of Quebec. In 1778, George Rogers Clark claimed Illinois County for Virginia. In a compromise, Virginia (and other states that made various claims) ceded the area to the new United States in the 1780s and it became part of the Northwest Territory, administered by the federal government and later organized as states. 
Prior to statehood
During the discussions leading up to Illinois's admission to the Union, the proposed northern boundary of the state was moved twice.  The original provisions of the Northwest Ordinance had specified a boundary that would have been tangent to the southern tip of Lake Michigan. Such a boundary would have left Illinois with no shoreline on Lake Michigan at all. However, as Indiana had successfully been granted a 10-mile (16 km) northern extension of its boundary to provide it with a usable lakefront, the original bill for Illinois statehood, submitted to Congress on January 23, 1818, stipulated a northern border at the same latitude as Indiana's, which is defined as 10 miles north of the southernmost extremity of Lake Michigan. However, the Illinois delegate, Nathaniel Pope, wanted more, and lobbied to have the boundary moved further north. The final bill passed by Congress included an amendment to shift the border to 42° 30' north, which is approximately 51 miles (82 km) north of the Indiana northern border. This shift added 8,500 square miles (22,000 km2) to the state, including the lead mining region near Galena. More importantly, it added nearly 50 miles of Lake Michigan shoreline and the Chicago River. Pope and others envisioned a canal that would connect the Chicago and Illinois rivers and thus connect the Great Lakes to the Mississippi.
The State of Illinois prior to the Civil War
In 1818, Illinois became the 21st U.S. state. The capital remained at Kaskaskia, headquartered in a small building rented by the state. In 1819, Vandalia became the capital, and over the next 18 years, three separate buildings were built to serve successively as the capitol building. In 1837, the state legislators representing Sangamon County, under the leadership of state representative Abraham Lincoln, succeeded in having the capital moved to Springfield,  where a fifth capitol building was constructed. A sixth capitol building was erected in 1867, which continues to serve as the Illinois capitol today.
Though it was ostensibly a " free state", there was nonetheless slavery in Illinois. The ethnic French had owned black slaves since the 1720s, and American settlers had already brought slaves into the area from Kentucky. Slavery was nominally banned by the Northwest Ordinance, but that was not enforced for those already holding slaves. When Illinois became a sovereign state in 1818, the Ordinance no longer applied, and about 900 slaves were held in the state. As the southern part of the state, later known as "Egypt" or "Little Egypt",   was largely settled by migrants from the South, the section was hostile to free blacks. Settlers were allowed to bring slaves with them for labor, but, in 1822, state residents voted against making slavery legal. Still, most residents opposed allowing free blacks as permanent residents. Some settlers brought in slaves seasonally or as house servants.  The Illinois Constitution of 1848 was written with a provision for exclusionary laws to be passed. In 1853, John A. Logan helped pass a law to prohibit all African Americans, including freedmen, from settling in the state. 
The winter of 1830–1831 is called the "Winter of the Deep Snow"; a sudden, deep snowfall blanketed the state, making travel impossible for the rest of the winter, and many travelers perished. Several severe winters followed, including the "Winter of the Sudden Freeze". On December 20, 1836, a fast-moving cold front passed through, freezing puddles in minutes and killing many travelers who could not reach shelter. The adverse weather resulted in crop failures in the northern part of the state. The southern part of the state shipped food north, and this may have contributed to its name: " Little Egypt", after the Biblical story of Joseph in Egypt supplying grain to his brothers. 
In 1832, the Black Hawk War was fought in Illinois and present-day Wisconsin between the United States and the Sauk, Fox (Meskwaki), and Kickapoo Indian tribes. It represents the end of Indian resistance to white settlement in the Chicago region.  The Indians had been forced to leave their homes and move to Iowa in 1831; when they attempted to return, they were attacked and eventually defeated by U.S. militia. The survivors were forced back to Iowa. 
By 1839, the Latter Day Saints had founded a utopian city called Nauvoo. Located in Hancock County along the Mississippi River, Nauvoo flourished, and soon rivaled Chicago for the position of the state's largest city. But in 1844, the Latter Day Saint movement founder Joseph Smith was killed in the Carthage Jail, about 30 miles away from Nauvoo. Following a succession crisis (Latter Day Saints), Brigham Young led most Latter Day Saints out of Illinois in a mass exodus to present-day Utah; after close to six years of rapid development, Nauvoo rapidly declined afterward.
After it was established in 1833, Chicago gained prominence as a Great Lakes port, and then as an Illinois and Michigan Canal port after 1848, and as a rail hub soon afterward. By 1857, Chicago was Illinois's largest city.  With the tremendous growth of mines and factories in the state in the 19th century, Illinois was the ground for the formation of labor unions in the United States.
In 1847, after lobbying by Dorothea L. Dix, Illinois became one of the first states to establish a system of state-supported treatment of mental illness and disabilities, replacing local almshouses. Dix came into this effort after having met J. O. King, a Jacksonville, Illinois businessman, who invited her to Illinois, where he had been working to build an asylum for the insane. With the lobbying expertise of Dix, plans for the Jacksonville State Hospital (now known as the Jacksonville Developmental Center) were signed into law on March 1, 1847. 
Civil War and after
During the American Civil War, Illinois ranked fourth in men who served (more than 250,000) in the Union Army, a figure surpassed by only New York, Pennsylvania, and Ohio. Beginning with President Abraham Lincoln's first call for troops and continuing throughout the war, Illinois mustered 150 infantry regiments, which were numbered from the 7th to the 156th regiments. Seventeen cavalry regiments were also gathered, as well as two light artillery regiments.  The town of Cairo, at the southern tip of the state at the confluence of the Mississippi and Ohio Rivers, served as a strategically important supply base and training center for the Union army. For several months, both General Grant and Admiral Foote had headquarters in Cairo.
During the Civil War, and more so afterwards, Chicago's population skyrocketed, which increased its prominence. The Pullman Strike and Haymarket Riot, in particular, greatly influenced the development of the American labor movement. From Sunday, October 8, 1871, until Tuesday, October 10, 1871, the Great Chicago Fire burned in downtown Chicago, destroying four square miles (10 km2). 
At the turn of the 20th century, Illinois had a population of nearly 5 million. Many people from other parts of the country were attracted to the state by employment caused by the expanding industrial base. Whites were 98% of the state's population.  Bolstered by continued immigration from southern and eastern Europe, and by the African-American Great Migration from the South, Illinois grew and emerged as one of the most important states in the union. By the end of the century, the population had reached 12.4 million.
The Century of Progress World's fair was held at Chicago in 1933. Oil strikes in Marion County and Crawford County led to a boom in 1937, and by 1939, Illinois ranked fourth in U.S. oil production. Illinois manufactured 6.1 percent of total United States military armaments produced during World War II, ranking seventh among the 48 states.  Chicago became an ocean port with the opening of the Saint Lawrence Seaway in 1959. The seaway and the Illinois Waterway connected Chicago to both the Mississippi River and the Atlantic Ocean. In 1960, Ray Kroc opened the first McDonald's franchise in Des Plaines (which still exists as a museum, with a working McDonald's across the street).
Illinois had a prominent role in the emergence of the nuclear age. In 1942, as part of the Manhattan Project, the University of Chicago conducted the first sustained nuclear chain reaction. In 1957, Argonne National Laboratory, near Chicago, activated the first experimental nuclear power generating system in the United States. By 1960, the first privately financed nuclear plant in the United States, Dresden 1, was dedicated near Morris. In 1967, Fermilab, a national nuclear research facility near Batavia, opened a particle accelerator, which was the world's largest for over 40 years. With eleven plants currently operating, Illinois leads all states in the amount of electricity generated from nuclear power.  
In 1961, Illinois became the first state in the nation to adopt the recommendation of the American Law Institute and pass a comprehensive criminal code revision that repealed the law against sodomy. The code also abrogated common law crimes and established an age of consent of 18.  The state's fourth constitution was adopted in 1970, replacing the 1870 document. 
The first Farm Aid concert was held in Champaign to benefit American farmers, in 1985. The worst upper Mississippi River flood of the century, the Great Flood of 1993, inundated many towns and thousands of acres of farmland. 
On August 28, 2017, Illinois Governor Bruce Rauner signed a bill into law that prohibited state and local police from arresting anyone solely due to their immigration status or due to federal detainers.   Some fellow Republicans criticized Rauner for his action, claiming the bill made Illinois a sanctuary state. 
Illinois's eastern border with Indiana consists of a north–south line at 87° 31′ 30″ west longitude in Lake Michigan at the north, to the Wabash River in the south above Post Vincennes. The Wabash River continues as the eastern/southeastern border with Indiana until the Wabash enters the Ohio River. This marks the beginning of Illinois's southern border with Kentucky, which runs along the northern shoreline of the Ohio River.  Most of the western border with Missouri and Iowa is the Mississippi River; Kaskaskia is an exclave of Illinois, lying west of the Mississippi and reachable only from Missouri. The state's northern border with Wisconsin is fixed at 42° 30′ north latitude. The northeastern border of Illinois lies in Lake Michigan, within which Illinois shares a water boundary with the state of Michigan, as well as Wisconsin and Indiana. 
Though Illinois lies entirely in the Interior Plains, it does have some minor variation in its elevation. In extreme northwestern Illinois, the Driftless Area, a region of unglaciated and therefore higher and more rugged topography, occupies a small part of the state. Southern Illinois includes the hilly areas around the Shawnee National Forest.
Charles Mound, located in the Driftless region, has the state's highest natural elevation above sea level at 1,235 feet (376 m). Other highlands include the Shawnee Hills in the south, and there is varying topography along its rivers; the Illinois River bisects the state northeast to southwest. The floodplain on the Mississippi River from Alton to the Kaskaskia River is known as the American Bottom.
Illinois has three major geographical divisions. Northern Illinois is dominated by Chicago metropolitan area, or Chicagoland, which is the city of Chicago and its suburbs, and the adjoining exurban area into which the metropolis is expanding. As defined by the federal government, the Chicago metro area includes several counties in Illinois, Indiana, and Wisconsin, and has a population of over 9.8 million. Chicago itself is a cosmopolitan city, densely populated, industrialized, the transportation hub of the nation, and settled by a wide variety of ethnic groups. The city of Rockford, Illinois's third-largest city and center of the state's fourth largest metropolitan area, sits along Interstates 39 and 90 some 75 miles (121 km) northwest of Chicago. The Quad Cities region, located along the Mississippi River in northern Illinois, had a population of 381,342 in 2011.
The midsection of Illinois is the second major division, called Central Illinois. It is an area of mainly prairie and known as the Heart of Illinois. It is characterized by small towns and medium–small cities. The western section (west of the Illinois River) was originally part of the Military Tract of 1812 and forms the conspicuous western bulge of the state. Agriculture, particularly corn and soybeans, as well as educational institutions and manufacturing centers, figure prominently in Central Illinois. Cities include Peoria; Springfield, the state capital; Quincy; Decatur; Bloomington-Normal; and Champaign- Urbana. 
The third division is Southern Illinois, comprising the area south of U.S. Route 50, including Little Egypt, near the juncture of the Mississippi River and Ohio River. Southern Illinois is the site of the ancient city of Cahokia, as well as the site of the first state capital at Kaskaskia, which today is separated from the rest of the state by the Mississippi River.   This region has a somewhat warmer winter climate, different variety of crops (including some cotton farming in the past), more rugged topography (due to the area remaining unglaciated during the Illinoian Stage, unlike most of the rest of the state), as well as small-scale oil deposits and coal mining. The Illinois suburbs of St. Louis, such as East St. Louis, are located in this region, and collectively, they are known as the Metro-East. The other somewhat significant concentration of population in Southern Illinois is the Carbondale-Marion-Herrin, Illinois Combined Statistical Area centered on Carbondale and Marion, a two-county area that is home to 123,272 residents.  A portion of southeastern Illinois is part of the extended Evansville, Indiana, Metro Area, locally referred to as the Tri-State with Indiana and Kentucky. Seven Illinois counties are in the area.
In addition to these three, largely latitudinally defined divisions, all of the region outside the Chicago Metropolitan area is often called " downstate" Illinois. This term is flexible, but is generally meant to mean everything outside the influence of the Chicago area. Thus, some cities in Northern Illinois, such as DeKalb, which is west of Chicago, and Rockford—which is actually north of Chicago—are sometimes incorrectly considered to be 'downstate'.
Illinois has a climate that varies widely throughout the year. Because of its nearly 400-mile distance between its northernmost and southernmost extremes, as well as its mid-continental situation, most of Illinois has a humid continental climate ( Köppen climate classification Dfa), with hot, humid summers and cold winters. The southern part of the state, from about Carbondale southward, has a humid subtropical climate (Koppen Cfa), with more moderate winters. Average yearly precipitation for Illinois varies from just over 48 inches (1,219 mm) at the southern tip to around 35 inches (889 mm) in the northern portion of the state. Normal annual snowfall exceeds 38 inches (965 mm) in the Chicago area, while the southern portion of the state normally receives less than 14 inches (356 mm).  The all-time high temperature was 117 °F (47 °C), recorded on July 14, 1954, at East St. Louis, and the all-time low temperature was −38 °F (−39 °C), recorded on January 31, 2019, during the January 2019 North American cold wave at a weather station near Mount Carroll,   and confirmed on March 5, 2019.  This followed the previous record of −36 °F (−38 °C) recorded on January 5, 1999, near Congerville.  Prior to the Mount Carroll record, a temperature of −37 °F (−38 °C) was recorded on January 15, 2009, at Rochelle, but at a weather station not subjected to the same quality control as official records.  
Illinois averages approximately 51 days of thunderstorm activity a year, which ranks somewhat above average in the number of thunderstorm days for the United States. Illinois is vulnerable to tornadoes, with an average of 35 occurring annually, which puts much of the state at around five tornadoes per 10,000 square miles (30,000 km2) annually.  While tornadoes are no more powerful in Illinois than other states, some of Tornado Alley's deadliest tornadoes on record have occurred in the state. The Tri-State Tornado of 1925 killed 695 people in three states; 613 of the victims died in Illinois. 
2019 Estimate  
The United States Census Bureau estimates that the population of Illinois was 12,671,821 in 2019, moving from the fifth-largest state to the sixth-largest state (losing out to Pennsylvania). Illinois's population declined by 69,259 people from July 2018 to July 2019, making it the worst decline of any state in the U.S. in raw terms. [ failed verification] This includes a natural increase since the last census of 462,146 people (i.e., 1,438,187 births minus 976,041 deaths) and an decrease due to net migration of 622,928 people. Immigration resulted in a net increase of 242,945 people, and migration from within the U.S. resulted in a net decrease of 865,873 people. 
Illinois is the most populous state in the Midwest region. Chicago, the third-most populous city in the United States, is the center of the Chicago metropolitan area or Chicagoland, as this area is nicknamed. Although Chicagoland comprises only 9% of the land area of the state, it contains 65% of the state's residents.
- 71.5% White American (63.7% non-Hispanic white, 7.8% White Hispanic)
- 14.5% Black or African American
- 0.3% American Indian and Alaska Native
- 4.6% Asian American
- 2.3% Multiracial American
- 6.8% some other race
According to 2018 U.S. Census Bureau estimates, Illinois's population was 71.7% White (60.9% Non-Hispanic White), 5.6% Asian, 5.6% Some Other Race, 14.1% Black or African American, 0.3% Native Americans and Alaskan Native, 0.1% Pacific Islander and 2.7% from two or more races.  The White population continues to remain the largest racial category in Illinois as Hispanics primarily identify as White (62.2%) with others identifying as Some Other Race (31.2%), Multiracial (3.9%), Black (1.5%), American Indian and Alaskan Native (0.8%), Asian (0.3%), and Hawaiian and Pacific Islander (0.1%).  By ethnicity, 17.3% of the total population is Hispanic-Latino (of any race) and 82.7% is Non-Hispanic (of any race). If treated as a separate category, Hispanics are the largest minority group in Illinois. 
|Racial composition||1990 ||2000 ||2010 |
Native Hawaiian and
other Pacific Islander
|Two or more races||—||1.9%||2.3%|
The state's most populous ethnic group, non-Hispanic white, has declined from 83.5% in 1970  to 60.90% in 2018.  As of 2011 [update], 49.4% of Illinois's population younger than age 1 were minorities (Note: Children born to white Hispanics or to a sole full or partial minority parent are counted as minorities). 
At the 2007 estimates from the U.S. Census Bureau, there were 1,768,518 foreign-born inhabitants of the state or 13.8% of the population, with 48.4% from Latin America, 24.6% from Asia, 22.8% from Europe, 2.9% from Africa, 1.2% from Canada, and 0.2% from Oceania. Of the foreign-born population, 43.7% were naturalized U.S. citizens, and 56.3% were not U.S. citizens.  In 2007, 6.9% of Illinois's population was reported as being under age 5, 24.9% under age 18 and 12.1% were age 65 and over. Females made up approximately 50.7% of the population. 
According to the 2007 estimates, 21.1% of the population had German ancestry, 13.3% had Irish ancestry, 8% had British ancestry, 7.9% had Polish ancestry, 6.4% had Italian ancestry, 4.6% listed themselves as American, 2.4% had Swedish ancestry, 2.2% had French ancestry, other than Basque, 1.6% had Dutch ancestry, and 1.4% had Norwegian ancestry.  Illinois also has large numbers of African Americans and Latinos (mostly Mexicans and Puerto Ricans).
Chicago, along the shores of Lake Michigan, is the nation's third largest city. In 2000, 23.3% of Illinois's population lived in the city of Chicago, 43.3% in Cook County, and 65.6% in the counties of the Chicago metropolitan area: Will, DuPage, Kane, Lake, and McHenry counties, as well as Cook County. The remaining population lives in the smaller cities and rural areas that dot the state's plains. As of 2000, the state's center of population was at , located in Grundy County, northeast of the village of Mazon.    
Births do not add up, because Hispanics are counted both by ethnicity and by race.
|Race||2013 ||2014 ||2015 ||2016 ||2017 ||2018 |
|White:||119,157 (75.9%)||119,995 (75.7%)||119,630 (75.6%)|
|Non-Hispanic White||85,866 (54.7%)||86,227 (54.4%)||85,424 (54.0%)||82,318 (53.3%)||78,925 (52.8%)||77,244 (53.3%)|
|Black||27,692 (17.6%)||28,160 (17.8%)||28,059 (17.7%)||25,619 (16.6%)||25,685 (17.2%)||24,482 (16.9%)|
|Asian||9,848 (6.3%)||10,174 (6.4%)||10,222 (6.5%)||10,015 (6.5%)||9,650 (6.5%)||9,452 (6.5%)|
|American Indian||234 (0.1%)||227 (0.1%)||205 (0.1%)||110 (0.0%)||133 (0.1%)||129 (0.1%)|
|Hispanic (of any race)||33,454 (21.3%)||33,803 (21.3%)||33,902 (21.4%)||32,635 (21.1%)||31,428 (21.0%)||30,362 (21.0%)|
|Total Illinois||156,931 (100%)||158,556 (100%)||158,116 (100%)||154,445 (100%)||149,390 (100%)||144,815 (100%)|
- Since 2016, data for births of White Hispanic origin are not collected, but included in one Hispanic group; persons of Hispanic origin may be of any race.
Chicago is the largest city in the state and the third-most populous city in the United States, with its 2010 population of 2,695,598. The U.S. Census Bureau currently lists seven other cities with populations of over 100,000 within Illinois. Based upon the Census Bureau's official 2010 population:  Aurora, a Chicago satellite town that eclipsed Rockford for the title of second-most populous city in Illinois; its 2010 population was 197,899. Rockford, at 152,871, is the third-largest city in the state, and is the largest city in the state not located within the Chicago suburbs. Joliet, located in metropolitan Chicago, is the fourth-largest city in the state, with a population of 147,433. Naperville, a suburb of Chicago, is fifth with 141,853. Naperville and Aurora share a boundary along Illinois Route 59. Springfield, the state's capital, comes in as sixth-most populous with 117,352 residents. Peoria, which decades ago was the second-most populous city in the state, is seventh with 115,007. The eighth-largest and final city in the 100,000 club is Elgin, a northwest suburb of Chicago, with a 2010 population of 108,188.
The most populated city in the state south of Springfield is Belleville, with 44,478 people at the 2010 census. It is located in the Illinois portion of Greater St. Louis (often called the Metro-East area), which has a rapidly growing population of over 700,000.
Other major urban areas include the Champaign-Urbana Metropolitan Area, which has a combined population of almost 230,000 people, the Illinois portion of the Quad Cities area with about 215,000 people, and the Bloomington-Normal area with a combined population of over 165,000.
Largest cities or towns in Illinois
2018 U.S. Census Bureau Estimate 
|7||Elgin||Kane / Cook||111,683|
The official language of Illinois is English,  although between 1923 and 1969, state law gave official status to "the American language". Nearly 80% of people in Illinois speak English natively, and most of the rest speak it fluently as a second language.  A number of dialects of American English are spoken, ranging from Inland Northern American English and African-American English around Chicago, to Midland American English in Central Illinois, to Southern American English in the far south.
Over 20% of Illinoians speak a language other than English at home, of which Spanish is by far the most widespread, at more than 12% of the total population.  A sizeable number of Polish speakers is present in the Chicago Metropolitan Area. Illinois Country French has mostly gone extinct in Illinois, although it is still celebrated in the French Colonial Historic District.
Roman Catholics constitute the single largest religious denomination in Illinois; they are heavily concentrated in and around Chicago, and account for nearly 30% of the state's population.  However, taken together as a group, the various Protestant denominations comprise a greater percentage of the state's population than do Catholics. In 2010 Catholics in Illinois numbered 3,648,907. The largest Protestant denominations were the United Methodist Church with 314,461, and the Southern Baptist Convention, with 283,519 members. Illinois has one of the largest concentrations of Missouri Synod Lutherans in the United States.
Illinois played an important role in the early Latter Day Saint movement, with Nauvoo, Illinois, becoming a gathering place for Mormons in the early 1840s. Nauvoo was the location of the succession crisis, which led to the separation of the Mormon movement into several Latter Day Saint sects. The Church of Jesus Christ of Latter-day Saints, the largest of the sects to emerge from the Mormon schism, has more than 55,000 adherents in Illinois today. 
Other Abrahamic religious communities
A significant number of adherents of other Abrahamic faiths can be found in Illinois. Largely concentrated in the Chicago metropolitan area, followers of the Muslim, Baháʼí, and Jewish religions all call the state home.  Muslims constituted the largest non-Christian group, with 359,264 adherents.  Illinois has the largest concentration of Muslims by state in the country, with 2,800 Muslims per 100,000 citizens.  The largest and oldest surviving Baháʼí House of Worship in the world is located in Wilmette, Illinois, The Chicago area has a very large Jewish community, particularly in the suburbs of Skokie, Buffalo Grove, Highland Park, and surrounding suburbs. Former Chicago Mayor Rahm Emanuel is the Windy City's first Jewish mayor.
As of February 2019, the unemployment rate in Illinois reached 4.2%. 
Illinois's major agricultural outputs are corn, soybeans, hogs, cattle, dairy products, and wheat. In most years, Illinois is either the first or second state for the highest production of soybeans, with a harvest of 427.7 million bushels (11.64 million metric tons) in 2008, after Iowa's production of 444.82 million bushels (12.11 million metric tons).  Illinois ranks second in U.S. corn production with more than 1.5 billion bushels produced annually.  With a production capacity of 1.5 billion gallons per year, Illinois is a top producer of ethanol, ranking third in the United States in 2011.  Illinois is a leader in food manufacturing and meat processing.  Although Chicago may no longer be " Hog Butcher for the World", the Chicago area remains a global center for food manufacture and meat processing,  with many plants, processing houses, and distribution facilities concentrated in the area of the former Union Stock Yards.  Illinois also produces wine, and the state is home to two American viticultural areas. In the area of The Meeting of the Great Rivers Scenic Byway, peaches and apples are grown. The German immigrants from agricultural backgrounds who settled in Illinois in the mid- to late 19th century are in part responsible for the profusion of fruit orchards in that area of Illinois.  Illinois's universities are actively researching alternative agricultural products as alternative crops.
Illinois is one of the nation's manufacturing leaders, boasting annual value added productivity by manufacturing of over $107 billion in 2006. As of 2011 [update], Illinois is ranked as the 4th-most productive manufacturing state in the country, behind California, Texas, and Ohio.  About three-quarters of the state's manufacturers are located in the Northeastern Opportunity Return Region, with 38 percent of Illinois's approximately 18,900 manufacturing plants located in Cook County. As of 2006, the leading manufacturing industries in Illinois, based upon value-added, were chemical manufacturing ($18.3 billion), machinery manufacturing ($13.4 billion), food manufacturing ($12.9 billion), fabricated metal products ($11.5 billion), transportation equipment ($7.4 billion), plastics and rubber products ($7.0 billion), and computer and electronic products ($6.1 billion). 
By the early 2000s, Illinois's economy had moved toward a dependence on high-value-added services, such as financial trading, higher education, law, logistics, and medicine. In some cases, these services clustered around institutions that hearkened back to Illinois's earlier economies. For example, the Chicago Mercantile Exchange, a trading exchange for global derivatives, had begun its life as an agricultural futures market. Other important non-manufacturing industries include publishing, tourism, and energy production and distribution.
Venture capitalists funded a total of approximately $62 billion in the U.S. economy in 2016. Of this amount, Illinois-based companies received approximately $1.1 billion. Similarly, in FY 2016, the federal government spent $461 billion on contracts in the U.S. Of this amount, Illinois-based companies received approximately $8.7 billion. 
Illinois is a net importer of fuels for energy, despite large coal resources and some minor oil production. Illinois exports electricity, ranking fifth among states in electricity production and seventh in electricity consumption. 
The coal industry of Illinois has its origins in the middle 19th century, when entrepreneurs such as Jacob Loose discovered coal in locations such as Sangamon County. Jacob Bunn contributed to the development of the Illinois coal industry, and was a founder and owner of the Western Coal & Mining Company of Illinois. About 68% of Illinois has coal-bearing strata of the Pennsylvanian geologic period. According to the Illinois State Geological Survey, 211 billion tons of bituminous coal are estimated to lie under the surface, having a total heating value greater than the estimated oil deposits in the Arabian Peninsula.  However, this coal has a high sulfur content, which causes acid rain, unless special equipment is used to reduce sulfur dioxide emissions.    Many Illinois power plants are not equipped to burn high-sulfur coal. In 1999, Illinois produced 40.4 million tons of coal, but only 17 million tons (42%) of Illinois coal was consumed in Illinois. Most of the coal produced in Illinois is exported to other states and countries. In 2008, Illinois exported three million tons of coal, and was projected to export nine million in 2011, as demand for energy grows in places such as China, India, and elsewhere in Asia and Europe.  As of 2010 [update], Illinois was ranked third in recoverable coal reserves at producing mines in the nation.  Most of the coal produced in Illinois is exported to other states, while much of the coal burned for power in Illinois (21 million tons in 1998) is mined in the Powder River Basin of Wyoming. 
Mattoon was recently chosen as the site for the Department of Energy's FutureGen project, a 275-megawatt experimental zero emission coal-burning power plant that the DOE just gave a second round of funding. In 2010, after a number of setbacks, the city of Mattoon backed out of the project. 
Illinois is a leading refiner of petroleum in the American Midwest, with a combined crude oil distillation capacity of nearly 900,000 barrels per day (140,000 m3/d). However, Illinois has very limited crude oil proved reserves that account for less than 1% of the U.S. total reserves. Residential heating is 81% natural gas compared to less than 1% heating oil. Illinois is ranked 14th in oil production among states, with a daily output of approximately 28,000 barrels (4,500 m3) in 2005.  
Nuclear power arguably began in Illinois with the Chicago Pile-1, the world's first artificial self-sustaining nuclear chain reaction in the world's first nuclear reactor, built on the University of Chicago campus. There are six operating nuclear power plants in Illinois: Braidwood, Byron, Clinton, Dresden, LaSalle, and Quad Cities.  With the exception of the single-unit Clinton plant, each of these facilities has two reactors. Three reactors have been permanently shut down and are in various stages of decommissioning: Dresden-1 and Zion-1 and 2. Illinois ranked first in the nation in 2010 in both nuclear capacity and nuclear generation. Generation from its nuclear power plants accounted for 12 percent of the nation's total.  In 2007, 48% of Illinois's electricity was generated using nuclear power.  The Morris Operation is the only de facto high-level radioactive waste storage site in the United States.
Illinois has seen growing interest in the use of wind power for electrical generation.  Most of Illinois was rated in 2009 as "marginal or fair" for wind energy production by the U.S. Department of Energy, with some western sections rated "good" and parts of the south rated "poor".  These ratings are for wind turbines with 50-meter (160 ft) hub heights; newer wind turbines are taller, enabling them to reach stronger winds farther from the ground. As a result, more areas of Illinois have become prospective wind farm sites. As of September 2009, Illinois had 1116.06 MW of installed wind power nameplate capacity with another 741.9 MW under construction.  Illinois ranked ninth among U.S. states in installed wind power capacity, and sixteenth by potential capacity.  Large wind farms in Illinois include Twin Groves, Rail Splitter, EcoGrove, and Mendota Hills. 
As of 2007, wind energy represented only 1.7% of Illinois's energy production, and it was estimated that wind power could provide 5–10% of the state's energy needs.   Also, the Illinois General Assembly mandated in 2007 that by 2025, 25% of all electricity generated in Illinois is to come from renewable resources. 
Illinois is ranked second in corn production among U.S. states, and Illinois corn is used to produce 40% of the ethanol consumed in the United States.  The Archer Daniels Midland corporation in Decatur, Illinois, is the world's leading producer of ethanol from corn.
The National Corn-to-Ethanol Research Center (NCERC), the world's only facility dedicated to researching the ways and means of converting corn (maize) to ethanol is located on the campus of Southern Illinois University Edwardsville.  
Tax is collected by the Illinois Department of Revenue. State income tax is calculated by multiplying net income by a flat rate. In 1990, that rate was set at 3%, but in 2010, the General Assembly voted for a temporary increase in the rate to 5%; the new rate went into effect on January 1, 2011; the personal income rate partially sunset on January 1, 2015, to 3.75%, while the corporate income tax fell to 5.25%.   Illinois failed to pass a budget from 2015 to 2017, after the 736-day budget impasse, a budget was passed in Illinois after lawmakers overturned Governor Bruce Rauner's veto; this budget raised the personal income rate to 4.95% and the corporate rate to 7%.  There are two rates for state sales tax: 6.25% for general merchandise and 1% for qualifying food, drugs, and medical appliances.  The property tax is a major source of tax revenue for local government taxing districts. The property tax is a local—not state—tax, imposed by local government taxing districts, which include counties, townships, municipalities, school districts, and special taxation districts. The property tax in Illinois is imposed only on real property.   
On May 1, 2019, the Illinois Senate voted to a approve a constitutional amendment to change from a flat tax rate to a graduated rate, in a 73–44 vote. The governor, J.B. Pritzker, approved the bill on May 27, 2019. It was scheduled  for a 2020 general election ballot vote  and requires 60 percent voter approval. It needed 71 votes to pass, with taxpayers making over $250,000 to be impacted. It also includes $100 million for property tax relief. 
As of 2017 Chicago had the highest state and local sales tax rate for a U.S. city with a populations above 200,000, at 10.250%.  The state of Illinois has the second highest rate of real estate tax: 2.31%, which is second only to New Jersey at 2.44%. 
Toll roads are a de facto user tax on the citizens and visitors to the state of Illinois. Illinois ranks seventh out of the 11 states with the most miles of toll roads, at 282.1 miles. Chicago ranks fourth in most expensive toll roads in America by the mile, with the Chicago Skyway charging 51.2 cents per mile.  Illinois also has the 11th highest gasoline tax by state, at 37.5 cents per gallon. 
Illinois has numerous museums; the greatest concentration of these are in Chicago. Several museums in Chicago are ranked as some of the best in the world. These include the John G. Shedd Aquarium, the Field Museum of Natural History, the Art Institute of Chicago, the Adler Planetarium, and the Museum of Science and Industry.
The modern Abraham Lincoln Presidential Library and Museum in Springfield is the largest and most attended presidential library in the country. The Illinois State Museum boasts a collection of 13.5 million objects that tell the story of Illinois life, land, people, and art. The ISM is among only 5% of the nation's museums that are accredited by the American Alliance of Museums. Other historical museums in the state include the Polish Museum of America in Chicago; Magnolia Manor in Cairo; Easley Pioneer Museum in Ipava; the Elihu Benjamin Washburne; Ulysses S. Grant Homes, both in Galena; and the Chanute Air Museum, located on the former Chanute Air Force Base in Rantoul.
The Chicago metropolitan area also hosts two zoos: The very large Brookfield Zoo, located about ten miles west of the city center in suburban Brookfield, contains more than 2,300 animals and covers 216 acres (87 ha). The Lincoln Park Zoo is located in huge Lincoln Park on Chicago's North Side, approximately 3 miles (4.8 km) north of the Loop. The zoo covers over 35 acres (14 ha) within the park.
Illinois is a leader in music education, having hosted the Midwest Clinic International Band and Orchestra Conference since 1946, as well being home to the Illinois Music Educators Association (IMEA), one of the largest professional music educator's organizations in the country. Each summer since 2004, Southern Illinois University Carbondale has played host to the Southern Illinois Music Festival, which presents dozens of performances throughout the region. Past featured artists include the Eroica Trio and violinist David Kim.
Chicago, in the northeast corner of the state, is a major center for music  in the midwestern United States where distinctive forms of blues (greatly responsible for the future creation of rock and roll), and house music, a genre of electronic dance music, were developed.
The Great Migration of poor black workers from the South into the industrial cities brought traditional jazz and blues music to the city, resulting in Chicago blues and "Chicago-style" Dixieland jazz. Notable blues artists included Muddy Waters, Junior Wells, Howlin' Wolf and both Sonny Boy Williamsons; jazz greats included Nat King Cole, Gene Ammons, Benny Goodman, and Bud Freeman. Chicago is also well known for its soul music.
In the 1980s and 1990s, heavy rock, punk, and hip hop also became popular in Chicago. Orchestras in Chicago include the Chicago Symphony Orchestra, the Lyric Opera of Chicago, and the Chicago Sinfonietta. 
John Hughes, who moved from Grosse Pointe to Northbrook, based many films of his in Chicago, and its suburbs. Ferris Bueller's Day Off, Home Alone, The Breakfast Club, and all his films take place in the fictional Shermer, Illinois (the original name of Northbrook was Shermerville, and Hughes's High School, Glenbrook North High School, is on Shermer Road). Most locations in his films include Glenbrook North, the former Maine North High School, the Ben Rose House in Highland Park, and the famous Home Alone house in Winnetka, Illinois.
Major league sports
As one of the United States' major metropolises, all major sports leagues have teams headquartered in Chicago.
- Two Major League Baseball teams are located in the state. The Chicago Cubs of the National League play in the second-oldest major league stadium ( Wrigley Field) and are widely known for having the longest championship drought in all of major American sport: not winning the World Series since 1908. However, this ended in 2016 when the Cubs finally won their first world series in 108 years.   That drought finally came to an end when the Cubs beat the Cleveland Indians in seven games to win the 2016 World Series. The Chicago White Sox of the American League won the World Series in 2005, their first since 1917. They play on the city's south side at Guaranteed Rate Field.
- The Chicago Bears football team has won nine total NFL Championships, the last occurring in Super Bowl XX on January 26, 1986.
- The Chicago Bulls of the NBA is one of the most recognized basketball teams in the world, largely as a result of the efforts of Michael Jordan, who led the team to six NBA championships in eight seasons in the 1990s.
- The Chicago Blackhawks of the NHL began playing in 1926, and became a member of the Original Six once the NHL dropped to that number of teams during World War II. The Blackhawks have won six Stanley Cups, most recently in 2015.
- The Chicago Fire is a member of MLS and has been one of the league's most successful and best-supported clubs since its founding in 1997, winning one league and four Lamar Hunt U.S. Open Cups in that timespan. The team played in Bridgeview, adjacent to Chicago from 2006 to 2019. The team now plays in Chicago.
Other top-level professional sports
- The Chicago Red Stars have played at the top level of U.S. women's soccer since their formation in 2009, except in the 2011 season. The team currently plays in the National Women's Soccer League, sharing a stadium with the Fire.
- The Chicago Sky have played in the Women's National Basketball Association, the sister league of the NBA, since 2006.
Minor league sports
Many minor league teams also call Illinois their home. They include:
- The Bloomington Edge of the Indoor Football League
- The Bloomington Flex of the Midwest Professional Basketball Association
- The Chicago Bandits of the NPF, a female softball league; have won four league titles, most recently in 2016
- The Chicago Red Stars of the NWSL, previously of Women's Professional Soccer League (WPS) and Women's Premier Soccer League (WPSL) 
- The Chicago Wolves are an AHL team playing in the suburb of Rosemont
- The Gateway Grizzlies of the Frontier League in Sauget, Illinois
- The Kane County Cougars of the Midwest League
- The Normal CornBelters of the Frontier League
- The Joliet Slammers of the Frontier League
- The Peoria Chiefs of the Midwest League
- The Peoria Rivermen are an SPHL team
- The Rockford Aviators of the Frontier League
- The Rockford IceHogs are an AHL team
- The Schaumburg Boomers of the Frontier League
- The Southern Illinois Miners based out of Marion in the Frontier League
- The Windy City Bulls, playing in the Chicago suburb of Hoffman Estates, of the NBA G League
The state features 13 athletic programs that compete in NCAA Division I, the highest level of U.S. college sports.
The two most prominent are the Illinois Fighting Illini and Northwestern Wildcats, both members of the Big Ten Conference and the only ones competing in one of the so-called " Power Five conferences". The Fighting Illini football team has won five national championships and three Rose Bowl Games, whereas the men's basketball team has won 17 conference seasons and played five Final Fours. Meanwhile, the Wildcats have won eight football conference championships and one Rose Bowl Game.
The Northern Illinois Huskies from DeKalb, Illinois compete in the Mid-American Conference winning four conference championships and earning a bid in the Orange Bowl along with producing Heisman candidate Jordan Lynch at quarterback. The Huskies are the state's only other team competing in the Football Bowl Subdivision, the top level of NCAA football.
Four schools have football programs that compete in the second level of Division I football, the Football Championship Subdivision. The Illinois State Redbirds (Normal, adjacent to Bloomington) and Southern Illinois Salukis (the latter representing Southern Illinois University's main campus in Carbondale) are members of the Missouri Valley Conference (MVC) for non-football sports and the Missouri Valley Football Conference (MVFC). The Western Illinois Leathernecks (Macomb) are full members of the Summit League, which does not sponsor football, and also compete in the MVFC. The Eastern Illinois Panthers (Charleston) are members of the Ohio Valley Conference (OVC).
The city of Chicago is home to four Division I programs that do not sponsor football. The DePaul Blue Demons, with main campuses in Lincoln Park and the Loop, are members of the Big East Conference. The Loyola Ramblers, with their main campus straddling the Edgewater and Rogers Park community areas on the city's far north side, compete in the MVC. The UIC Flames, from the Near West Side next to the Loop, are in the Horizon League. The Chicago State Cougars, from the city's south side, compete in the Western Athletic Conference.
Finally, two non-football Division I programs are located downstate. The Bradley Braves (Peoria) are MVC members, and the SIU Edwardsville Cougars (in the Metro East region across the Mississippi River from St. Louis) compete in the OVC.
Former Chicago sports franchises
The city was formerly home to several other teams that either failed to survive or belonged to leagues that folded.
- The Chicago Blitz, United States Football League 1983–1984
- The Chicago Sting, North American Soccer League 1975–1984 and Major Indoor Soccer League
- The Chicago Cougars, World Hockey Association 1972–1975
- The Chicago Rockers, Continental Basketball Association
- The Chicago Skyliners, American Basketball Association 2000–01
- The Chicago Bruisers, Arena Football League 1987–1989
- The Chicago Power, National Professional Soccer League 1984–2001
- The Chicago Blaze, National Women's Basketball League
- The Chicago Machine, Major League Lacrosse
- The Chicago Whales of the Federal Baseball League, a rival league to Major League Baseball from 1914 to 1916
- The Chicago American Giants of the Negro baseball league, 1910–1952
- The Chicago Bruins of the National Basketball League, 1939–1942
- The Chicago Studebaker Flyers of the NBL, 1942–43
- The Chicago American Gears of the NBL, 1944–1947
- The Chicago Stags of the Basketball Association of America, 1946–1950
- The Chicago Majors of the American Basketball League, 1961–1963
- The Chicago Express of the ECHL
- The Chicago Enforcers of the XFL pro football league
- The Chicago Fire, World Football League 1974
- The Chicago Winds, World Football League 1975
- The Chicago Hustle, Women's Professional Basketball League 1978–1981
- The Chicago Mustangs, North American Soccer League 1966–1967
- The Chicago Storm, Ultimate Soccer League 2004–2005
- The Chicago Rush, Arena Football League 2001–2013
The NFL's Arizona Cardinals, who currently play in the Phoenix suburb of Glendale, Arizona, played in Chicago as the Chicago Cardinals, until moving to St. Louis, Missouri after the 1959 season. An NBA expansion team known as the Chicago Packers in 1961–1962, and as the Chicago Zephyrs the following year, moved to Baltimore after the 1962–1963 season. The franchise is now known as the Washington Wizards.
Professional sports teams outside Chicago
The Peoria Chiefs and Kane County Cougars are minor league baseball teams affiliated with MLB. The Schaumburg Boomers and Lake County Fielders are members of the North American League, and the Southern Illinois Miners, Gateway Grizzlies, Joliet Slammers, Windy City ThunderBolts, and Normal CornBelters belong to the Frontier League.
Motor racing oval tracks at the Chicagoland Speedway in Joliet, the Chicago Motor Speedway in Cicero and the Gateway International Raceway in Madison, near St. Louis, have hosted NASCAR, CART, and IRL races, whereas the Sports Car Club of America, among other national and regional road racing clubs, have visited the Autobahn Country Club in Joliet, the Blackhawk Farms Raceway in South Beloit and the former Meadowdale International Raceway in Carpentersville. Illinois also has several short tracks and dragstrips. The dragstrip at Gateway International Raceway and the Route 66 Raceway, which sits on the same property as the Chicagoland Speedway, both host NHRA drag races.
Also, the state has hosted 13 editions of the U.S. Open (latest at Olympia Fields in 2003), six editions of the PGA Championship (latest at Medinah in 2006), three editions of the U.S. Women's Open (latest at The Merit Club), the 2009 Solheim Cup (at Rich Harvest Farms), and the 2012 Ryder Cup (at Medinah).
The John Deere Classic is a regular PGA Tour event played in the Quad Cities since 1971, whereas the Encompass Championship is a Champions Tour event since 2013. Previously, the LPGA State Farm Classic was an LPGA Tour event from 1976 to 2011.
Parks and recreation
The Illinois state parks system began in 1908 with what is now Fort Massac State Park, becoming the first park in a system encompassing more than 60 parks and about the same number of recreational and wildlife areas.
Areas under the protection of the National Park Service include: the Illinois and Michigan Canal National Heritage Corridor near Lockport,  the Lewis and Clark National Historic Trail, the Lincoln Home National Historic Site in Springfield, the Mormon Pioneer National Historic Trail, the Trail of Tears National Historic Trail, the American Discovery Trail,  and the Pullman National Monument. The federal government also manages the Shawnee National Forest and the Midewin National Tallgrass Prairie.
Law and politics
The government of Illinois, under the Constitution of Illinois, has three branches of government: executive, legislative and judicial. The executive branch is split into several statewide elected offices, with the governor as chief executive. Legislative functions are granted to the Illinois General Assembly. The judiciary is composed of the Supreme Court and lower courts.
The Illinois General Assembly is the state legislature, composed of the 118-member Illinois House of Representatives and the 59-member Illinois Senate. The members of the General Assembly are elected at the beginning of each even-numbered year. The Illinois Compiled Statutes (ILCS) are the codified statutes of a general and permanent nature.  
The executive branch is composed of six elected officers and their offices as well as numerous other departments.  The six elected officers are:  Governor, Lieutenant Governor, Attorney General, Secretary of State, Comptroller, and Treasurer. The government of Illinois has numerous departments, agencies, boards and commissions, but the so-called code departments provide most of the state's services.  
The Judiciary of Illinois is the unified court system of Illinois. It consists of the Supreme Court, Appellate Court, and Circuit Courts. The Supreme Court oversees the administration of the court system.
The administrative divisions of Illinois are counties, townships, precincts, cities, towns, villages, and special-purpose districts.  The basic subdivision of Illinois are the 102 counties.  Eighty-five of the 102 counties are in turn divided into townships and precincts.   Municipal governments are the cities, villages, and incorporated towns.  Some localities possess home rule, which allows them to govern themselves to a certain extent. 
Illinois is a Democratic stronghold.  Historically, Illinois was a political swing state, with near-parity existing between the Republican and the Democratic parties. However, in recent elections, the Democratic Party has gained ground, and Illinois has come to be seen as a solid "blue" state in presidential campaigns.   Votes from Chicago and most of Cook County have long been strongly Democratic. However, the " collar counties" (the suburbs surrounding Chicago's Cook County, Illinois), can be seen as moderate voting districts.   College towns like Carbondale, Champaign, and Normal also lean Democratic.
Republicans continue to prevail in the rural areas of northern and central Illinois, as well as southern Illinois outside of East St. Louis. From 1920 until 1972, Illinois was carried by the victor of each of these 14 presidential elections.  In fact, the state was long seen as a national bellwether,  supporting the winner in every election in the 20th century, except for 1916 and 1976. By contrast, Illinois has trended more toward the Democratic party, and has voted for their presidential candidates in the last six elections; in 2000, George W. Bush became the first Republican to win the presidency without carrying either Illinois or Vermont. Local politician and Chicago resident Barack Obama easily won the state's 21 electoral votes in 2008, with 61.9% of the vote. In 2010, incumbent governor Pat Quinn was re-elected with 47% of the vote, while Republican Mark Kirk was elected to the Senate with 48% of the vote. In 2012, President Obama easily carried Illinois again, with 58% to Republican candidate Mitt Romney's 41%. In 2014, Republican Bruce Rauner defeated Governor Quinn 50% to 46% to become Illinois's first Republican governor in 12 years after being sworn in on January 12, 2015, while Democratic senator Dick Durbin was re-elected with 53% of the vote. In 2016, Hillary Clinton carried Illinois with 55% of the vote, and Tammy Duckworth defeated incumbent Mark Kirk 54% to 40%. George W. Bush and Donald Trump are the only Republican presidential candidates to win without carrying either Illinois or Vermont. In 2018, Democrat JB Pritzker defeated the incumbent Bruce Rauner for the governorship with 54% of the vote.
History of corruption
Politics in the state have been infamous for highly visible corruption cases, as well as for crusading reformers, such as governors Adlai Stevenson and James R. Thompson. In 2006, former governor George Ryan was convicted of racketeering and bribery, leading to a six-and-a-half-year prison sentence. In 2008, then-Governor Rod Blagojevich was served with a criminal complaint on corruption charges, stemming from allegations that he conspired to sell the vacated Senate seat left by President Barack Obama to the highest bidder. Subsequently, on December 7, 2011, Rod Blagojevich was sentenced to 14 years in prison for those charges, as well as perjury while testifying during the case, totaling 18 convictions. Blagojevich was impeached and convicted by the legislature, resulting in his removal from office. In the late 20th century, Congressman Dan Rostenkowski was imprisoned for mail fraud; former governor and federal judge Otto Kerner, Jr. was imprisoned for bribery; Secretary of State Paul Powell was investigated and found to have gained great wealth through bribes, and State Auditor of Public Accounts (Comptroller) Orville Hodge was imprisoned for embezzlement. In 1912, William Lorimer, the GOP boss of Chicago, was expelled from the U.S. Senate for bribery and in 1921, Governor Len Small was found to have defrauded the state of a million dollars.   
U.S. presidential elections
Illinois has shown a strong presence in presidential elections. Three presidents have claimed Illinois as their political base when running for president: Abraham Lincoln, Ulysses S. Grant, and most recently Barack Obama. Lincoln was born in Kentucky, but he moved to Illinois at age 21. He served in the General Assembly and represented the 7th congressional district in the U.S. House of Representatives before his election to the presidency in 1860. Ulysses S. Grant was born in Ohio and had a military career that precluded settling down, but on the eve of the Civil War and approaching middle age, he moved to Illinois and thus utilized the state as his home and political base when running for president. Barack Obama was born in Hawaii and made Illinois his home after graduating from law school, and later represented Illinois in the U.S. Senate. He then became president in 2008, running as a candidate from his Illinois base.
Ronald Reagan was born in Illinois, in the city of Tampico, raised in Dixon, Illinois, and educated at Eureka College, outside Peoria. Reagan later moved to California during his young adulthood. He then became an actor, and later became California's Governor before being elected president.
Hillary Clinton was born and raised in the suburbs of Chicago and became the first woman to represent a major political party in the general election of the U.S. presidency. Clinton ran from a platform based in New York State.
African-American U.S. senators
Nine African-Americans have served as members of the United States Senate. Of which three have represented Illinois, the most of any single state: Carol Moseley-Braun,  Barack Obama,  and Roland Burris, who was appointed to replace Obama after his election to the presidency. Moseley-Braun was the first African-American woman to become a U.S. Senator.
Three families from Illinois have played particularly prominent roles in the Democratic Party, gaining both statewide and national fame.
The Stevenson family, initially rooted in central Illinois and later based in the Chicago metropolitan area, has provided four generations of Illinois officeholders.
- Adlai Stevenson I (1835–1914) was a Vice President of the United States, as well as a Congressman
- Lewis Stevenson (1868–1929), son of Adlai, served as Illinois Secretary of State.
- Adlai Stevenson II (1900–1965), son of Lewis, served as Governor of Illinois and as the U.S. Ambassador to the United Nations; he was also the Democratic party's presidential nominee in 1952 and 1956, losing both elections to Dwight Eisenhower.
- Adlai Stevenson III (1930–), son of Adlai II, served ten years as a United States Senator.
The Daley family's powerbase was in Chicago.
- Richard J. Daley (1902–1976) served as Mayor of Chicago from 1955 to his death.
- Richard M. Daley (1942–), son of Richard J, was Chicago's longest-serving mayor, in office from 1989 to 2011.
- William M. Daley (1948–), another son of Richard J, is a former White House Chief of Staff and has served in a variety of appointed positions.
The Pritzker family is based in Chicago and have played important roles in both the private and the public sectors.
- Jay Pritzker (1922–1999), co-founder of Hyatt Hotel based in Chicago.
- Penny Pritzker (born 1959), 38th United States Secretary of Commerce under President Barack Obama.
- J.B. Pritzker (born 1965), current and 43rd governor of Illinois and co-founder of the Pritzker Group.
Illinois State Board of education
The Illinois State Board of Education (ISBE) is autonomous of the governor and the state legislature, and administers public education in the state. Local municipalities and their respective school districts operate individual public schools, but the ISBE audits performance of public schools with the Illinois School Report Card. The ISBE also makes recommendations to state leaders concerning education spending and policies.
Primary and secondary schools
Education is compulsory for ages 7–17 in Illinois. Schools are commonly, but not exclusively, divided into three tiers of primary and secondary education: elementary school, middle school or junior high school, and high school. District territories are often complex in structure. Many areas in the state are actually located in two school districts—one for high school, the other for elementary and middle schools. And such districts do not necessarily share boundaries. A given high school may have several elementary districts that feed into it, yet some of those feeder districts may themselves feed into multiple high school districts.
Colleges and universities
Using the criterion established by the Carnegie Foundation for the Advancement of Teaching, there are eleven "National Universities" in the state. As of 19 August 2010 [update], six of these rank in the "first tier" (that is, the top quartile) among the top 500 National Universities in the United States, as determined by the U.S. News & World Report rankings: the University of Chicago (3), Northwestern University (10), the University of Illinois at Urbana–Champaign (41), Loyola University Chicago (89), the Illinois Institute of Technology (108), DePaul University (123), University of Illinois at Chicago (129), Illinois State University (149), Southern Illinois University Carbondale (153), and Northern Illinois University (194). 
The University of Chicago is continuously ranked as one of the world's top ten universities on various independent university rankings, and its Booth School of Business, along with Northwestern's Kellogg School of Management consistently rank within the top five graduate business schools in the country and top ten globally. The University of Illinois at Urbana–Champaign is often ranked among the best engineering schools in the world and in United States.
Illinois also has more than twenty additional accredited four-year universities, both public and private, and dozens of small liberal arts colleges across the state. Additionally, Illinois supports 49 public community colleges in the Illinois Community College System.
From 1962 until 1998, Chicago's O'Hare International Airport (ORD) was the busiest airport in the world, measured both in terms of total flights and passengers. While it was surpassed by Atlanta's Hartsfield in 1998 (as Chicago splits its air traffic between O'Hare and Midway airports, while Atlanta uses only one airport), with 59.3 million domestic passengers annually, along with 11.4 million international passengers in 2008,  O'Hare consistently remains one of the two or three busiest airports globally, and in some years still ranks number one in total flights. It is a major hub for both United Airlines and American Airlines, and a major airport expansion project is currently underway. Midway Airport (MDW), which had been the busiest airport in the world at one point until it was supplanted by O'Hare as the busiest airport in 1962, is now the secondary airport in the Chicago metropolitan area and still ranks as one of the nation's busiest airports. Midway is a major hub for Southwest Airlines and services many other carriers as well. Midway served 17.3 million domestic and international passengers in 2008. 
Illinois has an extensive passenger and freight rail transportation network. Chicago is a national Amtrak hub and in-state passengers are served by Amtrak's Illinois Service, featuring the Chicago to Carbondale Illini and Saluki, the Chicago to Quincy Carl Sandburg and Illinois Zephyr, and the Chicago to St. Louis Lincoln Service. Currently there is trackwork on the Chicago–St. Louis line to bring the maximum speed up to 110 mph (180 km/h), which would reduce the trip time by an hour and a half. Nearly every North American railway meets at Chicago, making it the largest and most active rail hub in the country. Extensive commuter rail is provided in the city proper and some immediate suburbs by the Chicago Transit Authority's 'L' system. One of the largest suburban commuter rail system in the United States, operated by Metra, uses existing rail lines to provide direct commuter rail access for hundreds of suburbs to the city and beyond.
In addition to the state's rail lines, the Mississippi River and Illinois River provide major transportation routes for the state's agricultural interests. Lake Michigan gives Illinois access to the Atlantic Ocean by way of the Saint Lawrence Seaway.
Interstate highway system
Illinois has the distinction of having the most primary (two-digit) interstates pass through it among all the 50 states with 13. Illinois also ranks third among the fifty states with the most interstate mileage, coming in after California and Texas, which are much bigger states in area. 
U.S. highway system
Among the U.S. highways that pass through the state, the primary ones are: US 6, US 12, US 14, US 20, US 24, US 30, US 34, US 36, US 40, US 41, US 45, US 50, US 51, US 52, US 54, US 60, US 62, and US 67.
- "Charles". NGS data sheet. U.S. National Geodetic Survey. Retrieved October 20, 2011.
- "Elevations and Distances in the United States". United States Geological Survey. 2001. Archived from the original on November 2, 2011. Retrieved October 21, 2011.
- Elevation adjusted to North American Vertical Datum of 1988.
- "Population and Housing Unit Estimates". United States Census Bureau. January 29, 2020. Retrieved January 30, 2020.
- Bureau, US Census. "U.S. Median Household Income Up in 2018 From 2017". The United States Census Bureau. Retrieved July 12, 2020.
"(5 ILCS 460/20) (from Ch. 1, par. 2901‑20) State Designations Act". Illinois Compiled Statutes. Springfield, Illinois: Illinois General Assembly. September 4, 1991.
Archived from the original on March 5, 2009. Retrieved April 10, 2009.
Sec. 20. Official language. The official language of the State of Illinois is English.
- Ohlemacher, Stephen (May 17, 2007). "Analysis ranks Illinois most average state". Carbondale, Illinois: The Southern Illinoisan. Associated Press. Archived from the original on January 14, 2009. Retrieved April 10, 2009.
- "What did Chicago look like in the early 1830s?". May 16, 2008. Archived from the original on December 26, 2007. Retrieved October 20, 2007.
- Ryburn-LaMonte, Terri (1999). "The Historical Development of Transportation in Illinois". Illinois Periodicals Online. Archived from the original on October 10, 2017.
- "Jazz". Encyclopedia of Chicago. Archived from the original on May 4, 2012. Retrieved May 19, 2012.
- "Blues". Encyclopedia of Chicago. Archived from the original on May 17, 2012. Retrieved May 19, 2012.
- "The History of Illinois License Plates". Cyberdriveillinois.com. Archived from the original on January 29, 2012. Retrieved February 15, 2012.
- "Slogan". Museum.state.il.us. Archived from the original on May 15, 2011. Retrieved February 7, 2011.
- "Archived copy". Archived from the original on June 23, 2010. Retrieved October 23, 2009.CS1 maint: archived copy as title ( link)
- Hodge, Frederick Webb (1911). Handbook of American Indians north of Mexico, Volume 1. Smithsonian Institution, Bureau of American Ethnology. p. 597. OCLC 26478613.
- Stewart, George R. (1967) . Names on the Land: A Historical Account of Place-Naming in the United States (Sentry (3rd) ed.). Houghton Mifflin.
- "Illinois Symbols". State of Illinois. Archived from the original on April 15, 2006. Retrieved April 20, 2006.
- Callary, Edward (2008). Place Names of Illinois. University of Illinois Press. p. 169. ISBN 978-0-252-03356-8.
- Costa, David J. (January 2007). "Three American Placenames: Illinois" (PDF). Society for the Study of the Indigenous Languages of the Americas Newsletter. 25 (4): 9–12. ISSN 1046-4476. Archived from the original (PDF) on July 16, 2011. Retrieved May 29, 2011.
- Willman, Harold Bowen; Atherton, Elwood; Buschbach, T. C.; Collinson, Charles William; Frye, John Chapman; Hopkins, M. E.; Lineback, Jerry Alvin; Simon, Jack A. (1975).
"Handbook of Illinois stratigraphy". Cite journal requires
Timothy R., Pauketat (2009). Cahokia : Ancient Americas Great City on the Mississippi.
Viking Press. pp. 23–34.
Cahokia was so large—covering three to five square miles—that archaeologists have yet to probe many portions of it. Its centerpiece was an open fifty-acre Grand Plaza, surrounded by packed-clay pyramids. The size of thirty-five football fields, the Grand Plaza was at the time the biggest public space ever conceived and executed north of Mexico ... a flat public square 1,600-plus feet in length and 900-plus feet in width.
- Skele, Mike (1988). The Great Knob. Studies in Illinois Archaeology. ISBN 978-0-942579-03-1. Archived from the original on September 24, 2015. Retrieved November 12, 2015.
- Snow, Dean (2010). Archaeology of Native North Americas. Upper Saddle River, NJ: Prentice Hall. pp. 201–203.
- Nash, Gary B. Red, White and Black: The Peoples of Early North America Los Angeles 2015. Chapter 1, p. 6
- Austin Alchon, Suzanne (2003). A pest in the land: new world epidemics in a global perspective. University of New Mexico Press. p. 59. ISBN 978-0-8263-2871-7.
- E. Hoxie, Encyclopedia of North American Indians (1996) 266–7, 506
- Nelson, Ronald E., ed. (1978). Illinois: Land and Life in the Prairie State. Dubuque, Iowa: Kendall/Hunt. ISBN 978-0-8403-1831-2.
- "Native Americans:American Indian Tribes of Illinois". Museum.state.il.us. October 2, 2002. Archived from the original on March 22, 2016. Retrieved February 27, 2016.
- de L'Isle, Guillaume (1718). "Carte de la Louisiane et du Cours du Mississipi. 1718". An Exhibition of Maps and Navigational Instruments on View. Tracy W. McGregor Room, Alderman Library: University of Virginia. Archived from the original on July 16, 2015. Retrieved January 25, 2010.
- Biles, Roger (2005). Illinois: A History of the Land and its People. DeKalb: Northern Illinois University Press. ISBN 978-0-87580-349-4.
- "Full Remarks from Dave M". Sancohis.org. March 16, 2010. Retrieved February 7, 2011.[ dead link]
- "Abraham Lincoln and Springfield—Abraham Lincoln's Classroom". Abrahamlincolnsclassroom.org. Archived from the original on May 30, 2012. Retrieved February 7, 2011.
- "The other Illinois: How Egypt lost its clout—Chicago Tribune". Articles.chicagotribune.com. June 24, 2001. Archived from the original on July 16, 2015. Retrieved April 29, 2012.
- "Southern Illinois Backroads Tourism: In Little Egypt it means bluffs, Superman, even scuba diving " Evansville Courier & Press". Courierpress.com. Archived from the original on January 17, 2013. Retrieved April 29, 2012.
- Paul Finkelman, Slavery and the Founders: Race and Liberty in the Age of Jefferson, (2001), p. 78
- James Pickett Jones, Black Jack: John A. Logan and Southern Illinois in the Civil War Era 1967 ISBN 0-8093-2002-9.
- Duff, Judge Andrew D. Egypt—Republished, Springhouse Magazine Archived September 16, 2012, at WebCite, accessed May 1, 2006.
- "Black Hawk War". Encyclopedia of Chicago. Archived from the original on August 22, 2012. Retrieved August 10, 2012.
- Lewis, James. "The Black Hawk War of 1832". Abraham Lincoln Historical Digitization Project. Archived from the original on August 1, 2012. Retrieved August 10, 2012.
- Norbury, Frank (Spring 1999). "Dorothea Dix and the Founding of Illinois's First Mental Hospital". Journal of the Illinois State Historical Society. 92 (1): 13–29. JSTOR 40193299.
- "Illinois Infantry, Cavalry, and Artillery Units" Archived August 18, 2018, at the Wayback Machine, Illinois in the Civil War, Retrieved November 26, 2006
- Roland Tweet, Miss Gale's Books: The Beginnings of the Rock Island Public Library, (Rock Island, IL: Rock Island Public Library, 1997), 15.
- "Illinois—Race and Hispanic Origin: 1800 to 1990". U.S. Census Bureau. Archived from the original on July 25, 2008.
- Peck, Merton J. & Scherer, Frederic M. The Weapons Acquisition Process: An Economic Analysis (1962) Harvard Business School p.111
- "ComEd and Electricity Related Messages for Economic Development" (PDF). Archived from the original (PDF) on July 8, 2011. Retrieved February 7, 2011.
- "Home | ComEd—An Exelon Company" (PDF). ComEd. Archived from the original (PDF) on September 14, 2013. Retrieved February 27, 2016.
- Painter, George (August 10, 2004). "The History of Sodomy Laws in the United States: Illinois". The Sensibilities of Our Forefathers. Gay & Lesbian Archives of the Pacific Northwest. Archived from the original on May 15, 2010. Retrieved January 12, 2012.
- Hillard, James (October 2008). "The Illinois Constitution: A Primer". Illinois Bar Journal. 96 (10): 494. Archived from the original on November 2, 2019. Retrieved November 2, 2019.
- Bernal, Rafael (August 28, 2017). "Illinois Governor Signs Immigration, Automatic Voter Registration Measures". The Hill. Archived from the original on September 3, 2019. Retrieved September 3, 2019.
- Tareen, Sophia (August 28, 2017). "Governor Signs Law Limiting Illinois Police on Immigration". ABC News (from the Associated Press). Archived from the original on September 10, 2017. Retrieved September 3, 2019.
- Singman, Brooke (August 28, 2017). "GOP Gov. Rauner Accused of Making Illinois a 'Sanctuary State' with New Law". Fox News. Archived from the original on July 9, 2018. Retrieved September 3, 2019.
- Wikisource. Illinois Constitution of 1818.
- Services, Eastern Region Geography, Information. "Elevations and Distances". egsc.usgs.gov. Archived from the original on November 30, 2018. Retrieved November 22, 2018.
- Horsley, A. Doyne (1986). Illinois: A Geography. Boulder: Westview Press. ISBN 978-0-86531-522-8.
- Illinois State Climatologist Office Archived February 7, 2006, at the Wayback Machine. Retrieved April 22, 2006.
- "US National Weather Service Central Illinois". Facebook. Retrieved January 31, 2019.
- "State Climate Extremes Committee (SCEC)". National Centers for Environmental Information. National Oceanic and Atmospheric Administration. Archived from the original on February 21, 2018. Retrieved April 30, 2019.
- "Illinois State Record Minimum Temperature at Mt. Carroll" (PDF). National Centers for Environmental Information. National Oceanic and Atmospheric Administration. March 5, 2019. Archived from the original (PDF) on June 8, 2019. Retrieved April 30, 2019.
- Hilyard, Scott (February 28, 2019). "Congerville about to lose its extreme cold state record". PJStar.com. Peoria, Illinois. Archived from the original on March 1, 2019. Retrieved March 1, 2019.
- Weather Underground (January 15, 2009). "Weather History for Rochelle, IL". Archived from the original on July 16, 2015. Retrieved January 2, 2014.
- " Annual average number of tornadoes, 1953–2004 Archived May 30, 2012, at WebCite", NOAA National Climatic Data Center. Retrieved October 24, 2006.
- PAH Webmaster (November 2, 2005). "NWS Paducah, KY: NOAA/NWS 1925 Tri-State Tornado Web Site—General Information". Archived from the original on October 2, 2006. Retrieved November 16, 2006.
- " Average Weather for Cairo, IL Archived July 10, 2014, at the Wayback Machine", weather.com
- " Chicago Weather Archived May 24, 2008, at the Wayback Machine", ustravelweather.com
- "Average Weather for Edwardsville, IL—Temperature and Precipitation". Weather.com. January 17, 2007. Archived from the original on May 16, 2012. Retrieved May 19, 2012.
- " Moline Weather Archived May 24, 2008, at the Wayback Machine", ustravelweather.com
- " Peoria Weather Archived May 24, 2008, at the Wayback Machine", ustravelweather.com
- " Rockford Weather Archived May 24, 2008, at the Wayback Machine", ustravelweather.com
- " Springfield Weather Archived May 24, 2008, at the Wayback Machine", ustravelweather.com
- "Resident Population Data—2010 Census". 2010.census.gov. Retrieved December 20, 2016.[ dead link]
- "Illinois population falls for fifth straight year with decline of 45,000". December 20, 2018. Archived from the original on December 21, 2018. Retrieved December 21, 2018.
- "B03002 HISPANIC OR LATINO ORIGIN BY RACE—Illinois—2018 American Community Survey 1-Year Estimates". U.S. Census Bureau. July 1, 2018. Retrieved November 25, 2019.
- Berg, Austin (December 20, 2017). "Census: Illinois loses title of 5th-largest state to Pennsylvania". Illinois Policy. Archived from the original on December 22, 2017. Retrieved December 20, 2017.
- "Estimates of the Components of Resident Population Change for the United States, Regions, States, and Puerto Rico: July 1, 2018 to July 1, 2019".
- Illinois QuickFacts from the US Census Bureau Archived April 1, 2009, at the Wayback Machine. Quickfacts.census.gov. Retrieved on July 21, 2013.
- "Historical Census Statistics on Population Totals By Race, 1790 to 1990, and By Hispanic Origin, 1970 to 1990, For The United States, Regions, Divisions, and States". Census.gov. July 25, 2008. Archived from the original on July 25, 2008. Retrieved September 4, 2017.
- "Population of Illinois: Census 2010 and 2000 Interactive Map, Demographics, Statistics, Quick Facts".[ permanent dead link]
- "2010 Census Data". Census.gov. Retrieved September 4, 2017.
- "Illinois QuickFacts". U.S. Census Bureau. Archived from the original on April 1, 2009.
- Exner, Rich (June 3, 2012). "Americans under age 1 now mostly minorities, but not in Ohio: Statistical Snapshot". The Plain Dealer. Archived from the original on July 14, 2016. Retrieved August 1, 2012.
- "Illinois Selected Social Characteristics in the United States: 2007". 2007 American Community Survey 1-Year Estimates. U.S. Census Bureau. 2007. Archived from the original on February 11, 2020. Retrieved April 9, 2009.
- "Illinois QuickFacts". U.S. Census Bureau. February 20, 2009. Archived from the original on April 1, 2009. Retrieved April 9, 2009.
- "Population and Population Centroid by State: 2000". American Congress on Surveying & Mapping. 2008. Archived from the original on October 20, 2001. Retrieved April 9, 2009.
- "Births: Final Data for 2013" (PDF). Cdc.gov. Archived (PDF) from the original on September 11, 2017. Retrieved September 4, 2017.
- "Births: Final Data for 2014" (PDF). Cdc.gov. Archived (PDF) from the original on February 14, 2017. Retrieved September 4, 2017.
- "Births: Final Data for 2015" (PDF). Cdc.gov. Archived (PDF) from the original on August 31, 2017. Retrieved September 4, 2017.
- "Archived copy" (PDF). Archived (PDF) from the original on June 3, 2018. Retrieved May 4, 2018.CS1 maint: archived copy as title ( link)
- "Archived copy" (PDF). Archived (PDF) from the original on February 1, 2019. Retrieved February 18, 2019.CS1 maint: archived copy as title ( link)
- "Data" (PDF). www.cdc.gov. Retrieved December 2, 2019.
- "Table 1: Annual Estimates of the Resident Population for Incorporated Places Over 100,000, Ranked by July 1, 2008 Population: April 1, 2000 to July 1, 2008 (SUB-EST2008-01)". 2008 Population Estimates. Population Division, United States Census Bureau. July 1, 2009. Archived from the original on July 18, 2009. Retrieved July 3, 2009.
- "U.S. Census Bureau QuickFacts: New York". New York—2018 Populations.
- "State Designations Act, Illinois Compiled Statutes". Archived from the original on March 19, 2015. Retrieved October 9, 2014.
- Ryan, Camille (August 2013). "Language Use in the United States: American Community Survey Reports" (PDF). Census.gov. United States Census Bureau. Archived from the original (PDF) on February 5, 2016. Retrieved March 30, 2014.
- "Illinois". Modern Language Association. Archived from the original on June 19, 2006. Retrieved October 9, 2014.
- "Religion in America: U.S. Religious Data, Demographics and Statistics". Pew Research Center. Archived from the original on March 29, 2016. Retrieved December 9, 2017.
- "Religious Landscape Study". Pew Research Center. May 11, 2015.
- "Roman Catholicism percentage of Catholics statistics—states compared—People data on StateMaster". Statemaster.com. May 15, 2012. Archived from the original on May 30, 2012. Retrieved May 19, 2012.
- "Facts and Statistics", Church News, 2020. Retrieved on March 30, 2020.
- "The Association of Religion Data Archives | County Membership Report". www.thearda.com. Archived from the original on November 12, 2013. Retrieved November 12, 2013.
- "The Association of Religion Data Archives | State Membership Report". www.thearda.com. Archived from the original on November 12, 2013. Retrieved November 12, 2013.
- Barooah, Jahnabi (June 27, 2012). "PHOTOS: Most And Least Muslim States In America". Huffington Post.
- "The Baháʼí House of Worship". Baháʼís of the United States. Archived from the original on March 6, 2019. Retrieved March 6, 2019.
- "Archived copy" (PDF). Archived (PDF) from the original on May 1, 2019. Retrieved May 1, 2019.CS1 maint: archived copy as title ( link)
- "GDP by State". Greyhill Advisors. Archived from the original on February 3, 2012. Retrieved September 16, 2011.
- "Moody's sees reason for optimism over Illinois economy". Crain's Chicago Business. February 18, 2019. Archived from the original on February 20, 2019. Retrieved February 20, 2019.
- Petrella, Dan. "Gov. J.B. Pritzker signs law raising Illinois's minimum wage to $15 an hour by 2025". chicagotribune.com. Archived from the original on February 20, 2019. Retrieved February 20, 2019.
- "Soybean Production by State 2008". Soy Stats. The American Soybean Association. 2009. Archived from the original on September 13, 2012. Retrieved January 19, 2010.
- "Ethanol Fact Sheet". Illinois Corn Growers Association. 2010. Archived from the original on July 23, 2011. Retrieved January 18, 2010.
- "Illinois—State Energy Profile Overview—U.S. Energy Information Administration (EIA)". Eia.gov. March 19, 2015. Archived from the original on July 16, 2015. Retrieved February 27, 2016.
- Facts About Illinois Agriculture Archived July 16, 2015, at WebCite, Illinois Department of Agriculture. Accessed online April 16, 2012
- "Meatpacking in Illinois History Archived June 13, 2012, at the Wayback Machine by Wilson J. Warren, Illinois History Teacher, 3:2, 2006. Access online April 16, 2012.
- Kathleen Walls. "Agri Trails". Americanroads.net. Archived from the original on March 4, 2016. Retrieved February 27, 2016.
- "DCEO: Home" (PDF). Ildceo.net. Archived from the original (PDF) on May 12, 2013. Retrieved February 27, 2016.
- "Manufacturing in Illinois" (PDF). Illinois Department of Commerce and Economic Opportunity. 2009. Archived from the original (PDF) on September 29, 2011. Retrieved January 19, 2010.
- Pradhan, Nitin (August 28, 2017). "Illinois—Want to be a Pioneer in Growing Companies, Jobs, and Competitiveness?". Medium. Archived from the original on September 5, 2017. Retrieved September 4, 2017.
- " Illinois in the Global Energy Marketplace" Archived May 17, 2008, at the Wayback Machine, Robert Finley, 2001. Illinois State Geological Survey publication.
- Illinois State Geological Survey. Coal in Illinois Archived February 12, 2012, at the Wayback Machine Retrieved December 4, 2008.
- "DCEO: Home" (PDF). Ildceo.net. Archived from the original (PDF) on October 29, 2013. Retrieved February 27, 2016.
- "Illinois Town Gives Up on Futurgen". Permianbasin360.com. August 12, 2010. Archived from the original on March 9, 2012. Retrieved April 29, 2012.
- United States Department of Energy. Petroleum Profile: Illinois Archived October 8, 2009, at the Wayback Machine. Retrieved April 4, 2006.
- "Illinois—U.S. Energy Information Administration (EIA)". Eia.gov. April 19, 2012. Archived from the original on April 15, 2012. Retrieved April 29, 2012.
- "Nuclear State Profiles". Eia.gov. Archived from the original on May 30, 2012. Retrieved April 29, 2012.
- "Illinois Nuclear Industry". U.S. Energy Information Administration. November 6, 2009. Archived from the original on November 9, 2004. Retrieved January 29, 2010.
- "Illinois Wind". Illinois Institute for Rural Affairs, Western Illinois University Illinoiswind.com Archived June 22, 2007, at the Wayback Machine
- "Illinois Wind Activities". EERE. U.S. Department of Energy. October 20, 2009. Archived from the original on February 9, 2010. Retrieved January 14, 2010.
- "U.S. Wind Energy Projects—Illinois". American Wind Energy Association. September 30, 2009. Archived from the original on January 5, 2010. Retrieved January 14, 2010.
- "Wind Power on the Illinois Horizon" Archived January 24, 2008, at the Wayback Machine, Rob Kanter, September 14, 2006. University of Illinois Environmental Council.
- "Illinois Renewable Electricity Profile". U.S. Energy Information Administration. 2007. Archived from the original on May 27, 2008. Retrieved January 15, 2010.
- Olbert, Lori (December 13, 2007). "Wind Farm Conference Tackles Complicated Issue". CIProud.com. WYZZ-TV/ WMBD-TV. Retrieved January 15, 2010.[ dead link]
- "ILFRA". Illinoisrfa.org. Archived from the original on March 4, 2016. Retrieved February 27, 2016.
- "Archived copy" (PDF). Archived from the original (PDF) on October 6, 2013. Retrieved September 12, 2013.CS1 maint: archived copy as title ( link)
- "BP Pledges $500 Million for Energy Biosciences Institute and Plans New Business to Exploit Research". Bp.com. June 14, 2006. Archived from the original on May 19, 2012. Retrieved May 19, 2012.
- "Gov. Blagojevich joins Gov. Schwarzenegger, top BP executives to celebrate launch of $500 million biosciences energy research partnership with University of Illinois Urbana-Champaign, UC-Berkeley". Illinois.gov. February 1, 2007. Archived from the original on May 26, 2012. Retrieved May 19, 2012.
- Pierog, Karen (January 12, 2011). "Illinois lawmakers pass big tax hike to aid budget". Reuters. Archived from the original on May 30, 2012. Retrieved February 7, 2011.
- Illinois Department of Revenue. Individual Income Tax Archived September 23, 2006, at the Wayback Machine. Retrieved January 30, 2011.
- Mendoza, Susana (September 18, 2018).
"Consequences of Illinois's 2015–2016 Budget Impasse and Fiscal Outlook". Illinois Comptroller. Archived from [/
https://illinoiscomptroller.gov/financial-data/find-a-report/special-fiscal/consequences-of-illinois-2015-2017-budget-impasse-and-fiscal-outlook/ the original] Check
|url=value ( help) on December 13, 2018. Retrieved July 26, 2019.
- Illinois Department of Revenue. Illinois Sales Tax Reference Manual (PDF) Archived May 27, 2008, at the Wayback Machine. p133. January 1, 2006.
- Sfondeles, Tina (May 27, 2019). "Graduated income tax question heads to ballot as House OKs constitutional amendment". www.chicagosuntimes.com. Chicago Sun Times. Archived from the original on May 30, 2019. Retrieved May 30, 2019.
- Kapos, Shia (May 28, 2019). "PRITZKER's BIG WIN—BRADY, MUNOZ stake in video gambling—ABORTION BILL fate uncertain". www.politico.com. Politico. Archived from the original on May 30, 2019. Retrieved May 30, 2019.
- Wall, Craig (May 27, 2019). "Illinois graduated income tax plan will go to voters after Governor JB Pritzker's bill passes the State House". abc7chicago.com. ABC 7. Archived from the original on May 31, 2019. Retrieved May 30, 2019.
- Walczak, Jared. "Sales Tax Rates in Major Cities, Midyear 2017". Taxfoundation.org. Tax Foundation. Archived from the original on March 31, 2019. Retrieved March 31, 2019.
- Kiernan, John S. "2019's Property Taxes by State". wallethub. Evolution Finance, Inc. Archived from the original on March 31, 2019. Retrieved March 31, 2019.
- "Most Expensive Toll Roads in the United States". ezfreightfactoring.com. EZ Freight Factoring. Archived from the original on March 31, 2019. Retrieved March 31, 2019.
- Stebbins, Samuel. "How much gas tax adds to cost of filling up your car in every state". usatoday. 24/7 Wall Street. Archived from the original on March 31, 2019. Retrieved March 31, 2019.
- Centerstage Chicago Archived July 8, 2008, at the Wayback Machine Retrieved on September 18, 2008
- Chicago Sinfonietta Website Archived January 20, 2017, at the Wayback Machine. Retrieved on November 7, 2008
- Mark McGuire Commentary (June 12, 2010). "Long look at Top 10 title droughts". Times Union. Archived from the original on February 20, 2011. Retrieved February 7, 2011.
- "The Longest Running Title Droughts in Sports". Bleacher Report. June 10, 2010. Archived from the original on July 8, 2011. Retrieved February 7, 2011.
- "Chicago Red Stars History—Chicago Red Stars". Chicagoredstars.com. Archived from the original on February 23, 2016. Retrieved February 27, 2016.
- "Illinois & Michigan Canal". National Park Service. Archived from the original on July 26, 2008. Retrieved July 15, 2008.
- "Illinois". National Park Service. Archived from the original on July 5, 2008. Retrieved July 15, 2008.
- Decker, John F.; Kopacz, Christopher (2012). Illinois Criminal Law: A Survey of Crimes and Defenses (5th ed.). LexisNexis. § 1.01. ISBN 978-0-7698-5284-3.
- Smith, Lori L.; Barkley, Daniel C.; Cornwall, Daniel C.; Johnson, Eric W.; Malcomb, J. Louise (2003). Tapping State Government Information Sources. Greenwood Publishing Group. p. 126. ISBN 978-1-57356-387-1. LCCN 2002044846.
- Uphoff, Judy Lee (2012). "The Governor and the Executive Branch" (PDF). In Lind, Nancy S.; Rankin, Erik (eds.). Governing Illinois: Your Connection to State and Local Government (4th ed.). Center Publications, Center for State Policy and Leadership, University of Illinois at Springfield. pp. 78–79. ISBN 978-0-938943-28-0. Archived from the original (PDF) on June 22, 2013.
- 20 ILCS 5
- Individual State Descriptions: 2007 (PDF), 2007 Census of Governments, United States Census Bureau, November 2012, pp. 89–97, archived (PDF) from the original on July 16, 2015, retrieved March 11, 2014
- Census 2007, p. 89.
- Illinois Regional Archives Depository System. "Name Index to Illinois Local Governments". Illinois State Archives. Illinois Secretary of State. Archived from the original on November 10, 2013. Retrieved November 11, 2013.
- Gove, Samuel Kimball; Nowlan, James Dunlap (1996). Illinois Politics & Government: The Expanding Metropolitan Frontier. Politics and Governments of the American States. Lincoln: University of Nebraska Press. pp. 155–156. ISBN 978-0-8032-7014-5. LCCN 95046017.CS1 maint: ref=harv ( link)
- McClelland, Edward (August 4, 2011). "Illinois: The Most Democratic State". NBC Chicago. Archived from the original on March 13, 2017. Retrieved December 29, 2016.
- "Suburb shift turns state blue / The Christian Science Monitor". CSMonitor.com. July 16, 2004. Archived from the original on July 16, 2015. Retrieved February 7, 2011.
- "Chicgao's [sic] dominance puts Illinois solidly in 'blue-state' America.—Chicago Tribune (Chicago, IL)". Highbeam.com. November 8, 2004. Archived from the original on August 27, 2011. Retrieved February 7, 2011.
- Pensoneau, Taylor (1997). Governor Richard Ogilvie: in the interest of the state. Southern Illinois University Press. p. 314. ISBN 978-0-8093-2148-3. Retrieved September 23, 2009.
- Gimpel, James G.; Jason E. Schuknecht (2004). Patchwork Nation: Sectionalism and Political Change in American Politics. University of Michigan Press. p. 488. ISBN 978-0-472-03030-9. Retrieved September 23, 2009.
- Meet the New Bellwether States: Ohio and Nevada—Smart Politics Archived July 16, 2015, at WebCite. Blog.lib.umn.edu. Retrieved on July 21, 2013.
- Illinois as a bellwether: So what? Archived July 15, 2015, at WebCite. Lib.niu.edu. Retrieved on July 21, 2013.
- Merriner, James L. (2004). Grafters and Goo Goos: corruption and reform in Chicago, 1833–2003. Carbondale: Southern Illinois University Press. ISBN 978-0-8093-2571-9. OCLC 52720998.
- "Moseley Braun, Carol". History, Art & Archives. United States House of Representatives. Retrieved October 6, 2020.
- "U.S. Senate: Art & History Home". Senate.gov. Archived from the original on July 2, 2018. Retrieved February 7, 2011.
- "Best Colleges 2010—National Universities Rankings". U.S. News & World Report. August 19, 2009. Archived from the original on January 5, 2011. Retrieved May 31, 2016.
- "O'Hare International Airport Activity Statistics" (PDF). City of Chicago: FlyChicago.com. March 27, 2009. Archived from the original (PDF) on January 1, 2010. Retrieved April 10, 2009.
- "Midway Airport Activity Statistics" (PDF). FlyChicago.com. City of Chicago. January 30, 2009. Archived from the original (PDF) on January 1, 2010. Retrieved April 10, 2009.
- "Interstate Frequently Asked Questions—50th Anniversary—Interstate System—Highway History—Federal Highway Administration". www.fhwa.dot.gov. Retrieved May 3, 2019.
- "Interstates by State". Interstate-Guide. February 2, 2016. Archived from the original on March 1, 2016. Retrieved February 27, 2016.
- Bridges, Roger D.; Davis, Rodney O. (1984). Illinois: its history & legacy. St. Louis: River City Publishers. ISBN 978-0-933150-86-7. OCLC 11814096.
- Cole, Arthur Charles (1987) . The era of the Civil War, 1848–1870. Urbana: University of Illinois Press. ISBN 978-0-252-01339-3. OCLC 14130434.
- Davis, James E. (1998). Frontier Illinois. Bloomington: Indiana University Press. ISBN 978-0-253-33423-7. OCLC 39182546.
- Grossman, James R.; Keating, Ann Durkin; Reiff, Janice L. (2005) . Electronic Encyclopedia of Chicago (Online ed.). Chicago: Chicago Historical Society, Newberry Library. ISBN 978-0-226-31015-2. OCLC 60342627. Retrieved January 28, 2009.
- Hallwas, John E., ed. (1986). Illinois literature: the nineteenth century. Macomb: Illinois Heritage Press. OCLC 14228886.
- Howard, Robert P. (1972). Illinois; a history of the Prairie State. Grand Rapids: W. B. Eerdmans Pub. Co. ISBN 978-0-8028-7025-4. OCLC 495362.
- Jensen, Richard E. (2001). Illinois: a history. Urbana: University of Illinois Press. ISBN 978-0-252-07021-1. OCLC 46769728.
- Keiser, John H. (1977). Building for the centuries: Illinois, 1865 to 1898. Urbana: University of Illinois Press. ISBN 978-0-252-00617-3. OCLC 2798051.
- Kilduff, Dorrell; Pygman, C. H. (1962). Illinois; History, government, geography. Chicago: Follett. OCLC 5223888.
- Kleppner, Paul (1988). Political atlas of Illinois. DeKalb: Northern Illinois University Press. ISBN 978-0-87580-136-0. OCLC 16755435.
- Meyer, Douglas K. (2000). Making the heartland quilt: a geographical history of settlement and migration in early-nineteenth-century Illinois. Carbondale: Southern Illinois University Press. ISBN 978-0-585-37905-0. OCLC 48139026.
- Nowlan, James D.; Gove, Samuel K.; Winkel, Richard J. (2010). Illinois Politics: A Citizen's Guide. Urbana: University of Illinois Press. ISBN 978-0-252-07702-9.
- Sutton, Robert P. (1976). The Prairie State; a documentary history of Illinois. Grand Rapids: Eerdmans. ISBN 978-0-8028-1651-1. OCLC 2603998.
- Walton, Clyde C. (1970). An Illinois reader. DeKalb: Northern Illinois University Press. ISBN 978-0-87580-014-1. OCLC 89905.
- Works Progress Administration (1983) . The WPA guide to Illinois: the Federal Writers' Project guide to 1930s Illinois. New York: Pantheon Books. ISBN 978-0-394-72195-8. OCLC 239788752.
- Illinois at Curlie
- Illinois Bureau of Tourism
- Illinois: Science In Your Backyard USGS
- Illinois State Energy Profile DOE, Energy Information Administration
- Illinois: State Fact Sheets USDA, Economic Research Service
- Illinois State Guide LOC, Virtual Programs & Services
- Biographies Of Governors of Illinois: 1818 to 1885 compiled by OnlineBiographies.info
- Illinois Highways Page by Richard Carlson
- State of Illinois research information guide from the University of Illinois at Urbana–Champaign
- Illinois State Agency Databases compiled by the Government Documents Round Table (GODORT) of the American Library Association
- Geographic data related to
List of U.S. states by date of admission to the Union
Admitted on December 3, 1818 (21st)