ILIllinois History

Around the year 1100 the largest city in what would become the United States stood on the Mississippi floodplain opposite present day St. Louis. Cahokia held somewhere between 10,000 and 20,000 people, a figure no city in the country would reach again until Philadelphia in the late 1700s. Its central earthwork, Monks Mound, still rises about 100 feet with a base covering roughly 14 acres, the largest earthen structure in the Americas north of Mexico. By about 1350 the site was empty.

Cahokia and the peoples of the Illinois country

Cahokia's builders left no writing and no recorded name for themselves. They raised more than a hundred mounds, laid out plazas covering dozens of acres, and set circles of red cedar posts that archaeologists call Woodhenge to track the solstice sunrises. Why it emptied is still argued over: repeated flooding of the bottomlands, deforestation of the bluffs for fuel and palisades, and the failure of whatever authority had commanded that much labour. By the time the French arrived, the Illinois Confederation held much of the region, a grouping of the Kaskaskia, Cahokia, Peoria, Michigamea and Tamaroa, with Sauk, Meskwaki, Potawatomi, Kickapoo and Miami pressing westward under the Haudenosaunee wars.

Three flags over the Illinois country

Jacques Marquette and Louis Jolliet descended the Mississippi in 1673 and returned up the Illinois River. La Salle followed with Fort Crèvecoeur near present day Peoria in 1680 and Fort St. Louis atop Starved Rock in 1682. French villages took root at Cahokia in 1699, Kaskaskia in 1703 and Prairie du Rocher, and their farmers grew wheat that went downriver to feed New Orleans.

The Treaty of Paris in 1763 handed everything east of the Mississippi to Britain. On 4 July 1778 George Rogers Clark took Kaskaskia for Virginia without firing a shot, and Virginia governed the region as Illinois County before ceding its claim to Congress. The Northwest Ordinance of 1787 barred slavery north of the Ohio, and Illinois Territory was split off in 1809 with Kaskaskia as its capital.

A boundary moved 41 miles, and a vote on slavery

Congress admitted Illinois on 3 December 1818 as the 21st state. Congress required 60,000 residents; the territorial count came to about 34,620 before officials padded it by enumerating travellers on the roads. The more consequential fight was over the northern line. As drawn under the Northwest Ordinance it would have run west from the southern tip of Lake Michigan, leaving the future site of Chicago in Wisconsin. Territorial delegate Nathaniel Pope had it moved 41 miles north to 42 degrees 30 minutes, adding roughly 8,500 square miles and a lakefront. His stated reason was strategic: a state with a Great Lakes port would face north and east, and its commerce would bind it to the free states.

Slavery persisted in the free state anyway. French owners had held people in bondage since before 1787, the salt works at Shawneetown ran on leased slaves under a legislative exception, and indentures of 40 and 99 years worked as slavery under another word. In 1824 a referendum on calling a convention to legalise it outright was defeated 6,640 to 4,972, in a campaign led by Governor Edward Coles, a Virginian who had freed his own slaves on the way west and given them Illinois farmland. In 1839 the capital moved from Vandalia to Springfield through the manoeuvring of the Sangamon County delegation known as the Long Nine, one of whom was Abraham Lincoln.

Lincoln's state and the Union's western hinge

Latter-day Saints expelled from Missouri built Nauvoo on a bend of the Mississippi, and by 1844 it rivalled Chicago in population. Joseph Smith was killed by a mob at the Carthage jail on 27 June 1844, and the community left for the Great Basin in 1846. The seven Lincoln and Douglas debates, from Ottawa in August 1858 to Alton in October, were fought over whether slavery could be kept out of the territories. Douglas held the Senate seat; Lincoln took the presidency two years later. Illinois then sent about 259,000 men to the Union armies. Cairo, at the junction of the Ohio and the Mississippi, became Ulysses Grant's staging base for the river campaigns that cut the Confederacy in half. Southern Illinois, settled from Kentucky and Tennessee, produced enough Copperhead sentiment that Governor Richard Yates prorogued the legislature in 1863 to stop a resolution for a negotiated peace.

Fire, stockyards and the making of Chicago

The Illinois and Michigan Canal opened in 1848 and joined Lake Michigan to the Illinois River and so to the Mississippi, making Chicago the hinge between eastern railroads and western grain. The Union Stock Yards opened on Christmas Day 1865 and grew into a square mile of pens, and refrigerated rail cars let a few packers dominate American meat until Upton Sinclair's novel The Jungle provoked the Meat Inspection Act in 1906. Fire came first: between 8 and 10 October 1871 roughly 3.3 square miles burned, about 300 people died and 100,000 were left homeless, and the rebuilding produced the first steel framed skyscraper, the Home Insurance Building of 1885. A bomb at Haymarket Square on 4 May 1886 and the Pullman strike of 1894 marked the cost of the boom.

The Great Migration and the century since

From 1916 onward the Illinois Central carried hundreds of thousands of Black southerners north out of Mississippi and Louisiana. Chicago's Black population rose from about 44,000 in 1910 to 234,000 in 1930 and past 800,000 by 1960. Reaction was violent: 38 people died in the riot that began on 27 July 1919 after a Black teenager, Eugene Williams, drifted across an unofficial line at a Lake Michigan beach and was stoned. Restrictive covenants and then federal redlining fixed the residential map that Martin Luther King Jr. came to challenge in 1966, when he took a flat in North Lawndale and was struck by a rock while marching through Marquette Park. On 2 December 1942, in a squash court under the stands of Stagg Field, Enrico Fermi's team brought Chicago Pile-1 to the first self-sustaining nuclear chain reaction. Heavy industry then left as abruptly as it had arrived: Wisconsin Steel shut without notice in 1980, and US Steel South Works, which had employed 20,000 people, closed in 1992.

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