Chicago (IPA: /ʃɪˈkɑːgoʊ/) is the largest city in the state of Illinois, the largest in the Midwest, and, with a population of nearly 3 million people located almost entirely in Cook County (a portion of the city's O'Hare International Airport overlaps into DuPage County), is the third-most populous city in the United States. The Chicago metropolitan area (commonly referred to as Chicagoland) has a population of over 9.7 million people in Illinois, Wisconsin and Indiana, making it also the third largest metropolitan area in the U.S.[2] Adjacent to Lake Michigan, it is the largest city located on the Great Lakes and among the world's twenty-five largest urban areas by population. Chicago has been classified as an alpha world city for its worldwide economic and cultural influence.

Incorporated as a city in 1837 after being founded in 1833 at the site of a portage between the Great Lakes and the Mississippi River watershed, it soon became a major transportation hub in North America and quickly became the business and financial capital of the American Midwest. Since the Chicago World's Fair of 1893, it has been regarded as one of the ten most influential cities in the world. [3] Among the fields in which its influence has been seen are physics where Chicago Pile-1 served as the world's first artificial nuclear reactor, and architecture where it has contributed Chicago school architecture. It also boasts some of the world's tallest buildings (Sears Tower, Aon Center, and Hancock Center), and some of the tallest skyscrapers under construction (Chicago Spire and Trump International Hotel and Tower). The University of Chicago is a leader in many fields and has contributed its own Chicago schools such as Chicago school economics.

Today, Chicago boasts a rich diversity of cultural offerings: teams from each of the major league sports (Bears, Blackhawks, Bulls, Cubs, and White Sox), a financial district anchored by the Chicago Mercantile Exchange located at the foot of LaSalle Street in the Chicago Board of Trade Building, the shopping of the Magnificent Mile, and a blossoming Theatre district. Noted among Chicago Landmarks are Wrigley Field, and Buckingham Fountain. The Magnificent Mile is a fitting tribute for a city that has revolutionized retail merchandising with Aaron Montgomery Ward perfecting mail order catalogs and Marshall Field inventing the money-back guarantee, bridal registry and being the first to use posted prices on goods.

Chicago is served by two major international airports, Chicago Midway International Airport and O'Hare International Airport (the world's second busiest in terms of passengers) as well as the internationally recognized Chicago 'L' system of rapid transit. Chicago was once the capital of the railroad industry and the nation's meatpacking was hubbed at the Union Stock Yards. Chicago has seen the gangland era Al Capone and has a history of Chicago-style politics which goes back to getting Abraham Lincoln nominated for to be United States President at the Wigwam and continued through the Cook County Democratic Organization run by Chicago Mayor Richard J. Daley. More recent Democrats from Cook County include the first African-American female United States Senator, Carol Mosley-Braun, and the first leading African-American United States Presidential contender, Senator Barack Obama.

History
Main articles: History of Chicago, Political history of Chicago, Windy City, Origin of Name (Chicago), and List of mayors of Chicago

Northern Chicago seen from Spot satelliteThe name "Chicago" is the French rendering of the Miami-Illinois name shikaakwa, meaning “wild leek”.[4][5][6] Etymologically, the sound /shikaakwa/ in Miami-Illinois literally means 'striped skunk', and was a reference to wild leek, or the smell of onions.[5] The name was initially applied to the river, but later came to denote what is presently the site of city. The sound Chicago is said[who?] to be the result of a French mis-transcription of the original sound by Louis Hennepin, a Catholic priest, missionary and explorer, who in 1683 first placed the place name 'Chicago' on a map.[citation needed]

During the mid-18th century the area was inhabited primarily by Potawatomis, who had taken the place of the Miami and Sauk and Fox peoples. The first permanent settler in Chicago, Haitian Jean Baptiste Pointe du Sable, arrived in the 1770s, married a Potawatomi woman, and founded the area’s first trading post. In 1803 the United States Army built Fort Dearborn, which was destroyed in the 1812 Fort Dearborn massacre. The Ottawa, Ojibwa, and Potawatomi later ceded the land to the United States in the 1816 Treaty of St. Louis. On August 12, 1833, the Town of Chicago was organized with a population of 350. Within seven years it grew to a population of over 4,000. The City of Chicago was incorporated on March 4, 1837.

The city began its step toward regional primacy as an important transportation hub between the eastern and western United States. Begun in 1836, Chicago’s first railway, Galena and Chicago Union Railroad, opened in 1848, a year which also marked the opening of the Illinois and Michigan Canal. The canal allowed steamboats and sailing ships on the Great Lakes to connect to the Mississippi River. A flourishing economy brought many new residents from rural communities as well as immigrants from abroad. The city’s manufacturing and retail sectors became dominant among Midwestern cities and subsequently influenced the American economy, particularly in meatpacking, with the advent of the refrigerated rail car and the regional centrality of the city's Union Stock Yards.[7]

During its first century as a city, Chicago grew at a rate that ranked among the fastest growing in the world. Within the span of forty years, the city's population grew from slightly under 30,000 to over 1 million by 1890. By the close of the 19th century, Chicago was the fifth largest city in the world,[8] and the largest of the cities that didn't exist at the dawn of the century. Within fifty years of the Chicago Fire, the population had tripled to over 3 million.[9]


Artist's rendering of the Great Chicago Fire of 1871.In February of 1856, the Chesbrough plan for the building of Chicago’s (and indeed the United States’) first comprehensive sewerage system was approved by the Common Council;[10] a project that necessitated the physical raising of much of central Chicago to a new grade. Untreated sewage and industrial waste now flowed into the Chicago River, thence into Lake Michigan, polluting the primary source of fresh water for the city. The city responded by tunneling two miles (3 km) out into Lake Michigan to newly built water cribs. Nonetheless, spring rains continued to carry polluted water as far out as the water intakes. In 1900, the problem of sewage was largely resolved when Chicago undertook an innovative engineering feat. The city actually reversed the flow of the river, a process that started with the construction and improvement of the Illinois and Michigan Canal and completed with the finishing of the Chicago Sanitary and Ship Canal) leading to the Illinois River which joins the Mississippi River.


The Chicago Water Tower, one of the few surviving buildings after the Great Chicago Fire of 1871.After the Great Chicago Fire of 1871 destroyed a third of the city, including the entire central business district, Chicago experienced rapid rebuilding and growth.[11] During Chicago's rebuilding period, the world's first skyscraper was constructed in 1885 using steel-skeleton construction.

In 1893, Chicago hosted the World's Columbian Exposition on former marshland at the present location of Jackson Park. The Exposition drew 27.5 million visitors, and is considered among the most influential world's fairs in history.[12] The University of Chicago had been founded one year earlier in 1892 on the same South Side location. The term "midway" for a fair or carnival referred originally to the Midway Plaisance, a strip of park land that still runs through the University of Chicago campus and connects Washington and Jackson Parks.

The city was the site of labor conflicts and unrest during this period, which included the Haymarket affair on May 4, 1886. Concern for social problems among Chicago’s lower classes led Jane Addams to be a co-founder of Hull House in 1889, the first of what were called settlement houses. Programs developed there became a model for the new field of social work. The city also invested in many large, well-landscaped municipal parks, which also included public sanitation facilities.

The 1920s brought notoriety to Chicago as gangsters, including the notorious Al Capone, battled each other and law enforcement on the city streets during the Prohibition era. The 1920s also saw a major expansion in industry. The availability of jobs attracted African Americans from the South. Arriving in the tens of thousands during the Great Migration, the cultural impact of the newcomers was immense. It was during this wave that Chicago became a center for jazz, with King Oliver leading the way.[13]

In 1933, Mayor Anton Cermak was assassinated while in Miami with President Franklin D. Roosevelt.

On December 2, 1942, physicist Enrico Fermi conducted the world’s first controlled nuclear reaction at the University of Chicago as part of the top-secret Manhattan Project.

The Sears Tower, at 108 Stories, stands as Chicago's tallest building since its completion in 1974 and is the tallest free standing structure in the United States.Mayor Richard J. Daley was elected in 1955, in the era of machine politics. Starting in the 1960s, many upper- and middle-class citizens started leaving the city for the suburbs, as was the case in many cities across the country. It took the heart out of many residential neighborhoods, leaving impoverished and disadvantaged citizens behind. Structural changes in industry caused heavy losses of jobs for lower skilled workers.

The city hosted the tumultuous 1968 Democratic National Convention, which featured physical confrontations both inside and outside the convention hall, including full-scale police riots in city streets. Major construction projects, including the Sears Tower (which in 1974 became the world’s tallest building), McCormick Place, and O'Hare Airport, were undertaken during Richard J. Daley's tenure. When he died, Michael Anthony Bilandic was mayor for three years. His loss in a primary election has been attributed to the city’s inability to properly plow city streets during a heavy snowstorm. In 1979, Jane Byrne, the city’s first female mayor, was elected. She popularized the city as a movie location and tourist destination.

In 1983 Harold Washington became the first African American to be elected to the office of mayor, in one of the closest mayoral elections in Chicago. After Washington won the Democratic primary, racial motivations caused a few Democratic alderman and ward committeemen to back the Republican candidate Bernard Epton, who ran on the slogan Before it’s too late, a thinly veiled appeal to fear.[14] Washington’s term in office saw new attention given to poor and minority neighborhoods. His administration reduced the longtime dominance of city contracts and employment by ethnic whites.

Current mayor Richard M. Daley, son of the late Richard J. Daley, was first elected in 1989. He has led many progressive changes to the city, including improving parks; creating incentives for sustainable development, including green roofs; and major new developments. Since the 1990s, the city has undergone a revitalization in which some lower class neighborhoods have been transformed into pricey neighborhoods as new middle class residents have settled in the city.