The Great Chicago Fire Of 1871: Map, Timeline & Aftermath

Chicago, Illinois October 8–10, 1871 The Conflagration Edition

On the night of October 8, 1871, a fire that began in a barn on Chicago’s West Side burned for some thirty hours, crossed the river twice, and consumed the heart of the city. The world knows it as the Great Chicago Fire.

This page lays the whole event out: what the fire took, why a wooden city was primed to burn, a map of its path, the hour-by-hour timeline, the deadlier fire that struck Wisconsin the same night, and the six places where 1871 is still part of daily Chicago. The three-year fight over the rebuilding has its own page.

Lithograph of crowds fleeing across the Randolph Street bridge as Chicago burns behind them — **“Chicago in Flames.”** Citizens flee northeast across the Randolph Street bridge as the business district burns. Currier & Ives lithograph, 1871 · via Wikimedia Commons (public domain).

The Reckoning

What the fire took

~300Lives lostEstimated dead, and long thought an undercount: whole families vanished, and transient workers were never counted.

17,500Buildings destroyedWood cottages, mills, mansions and the business district together; the count is a period estimate.

100kLeft homelessAbout 100,000 people — roughly three in ten Chicagoans. The 1870 census had counted 298,977 residents.

2,112Acres burnedA scar about 4 miles long and two-thirds of a mile wide — some 3.3 square miles.

$200MIn damagesIn 1871 dollars, and the figure is disputed: standard tallies run from $200 million to $222 million. All agree it was roughly a third of the city’s assessed value.

30hOf burningFrom the first alarm Sunday night until rain quenched the flames Tuesday. Accounts run from about thirty hours to thirty-six, depending on when you stop counting.

The Tinderbox

Why a wooden city was ready to burn

The fire spread the way it did because Chicago in October 1871 was about as dry, as wooden, and as poorly defended as it would ever be. The figures below follow the National Weather Service’s reconstruction of that autumn and contemporary accounts of the department’s week.

0.11″Rain in three weeksInches of rain in the 22 days before the fire — it fell once. The three months before it brought 3.55 inches, the second-driest such stretch on record in the Weather Service’s reconstruction.

2 in 3Buildings of woodAnd so were the sidewalks — and many of the streets themselves, paved with pine blocks set in tar.

18hAlready on their feetSome crews had fought a four-block blaze through Saturday night; the roughly 190-man department was spent when Sunday’s alarm came.

Taken together, those conditions amount to an argument about the whole disaster — an argument, because nobody can prove it. A spark explains how the fire started. The drought, the timber and the worn-out department explain why it did not stop. That is why the question Chicago has argued over for more than 150 years — who lit it — may be the least useful one to ask.

The Path of the Flames

How the fire moved across the city

A river should have stopped it. Instead, driven by a hot southwest wind, the fire crossed the Chicago River twice — over the South Branch into the business district, then over the Main Branch into the North Side — and ran until it met open prairie, the lakeshore, and rain. It could do that because the water was about the only thing on the river that would not burn. The banks carried lumberyards, coal heaps, gasworks and wooden bridges, and the wind threw embers far enough ahead to find them. The shaded band traces the reconstructed burn perimeter; the river and shoreline are drawn from real geographic coordinates.

Burned district — ~2,112 acres Origin: O’Leary barn Direction of spread Notable survivor

The burn perimeter is an approximate reconstruction from period survey maps. The 1871 shoreline lay somewhat west of today’s — much of the modern lakefront is landfill, some of it fire debris pushed into the lake.

Hour by Hour

Thirty hours, October 8–10

Sun · Oct 8~9:00 p.m.

A fire in the barn

Flames break out in or near a barn behind the O’Leary cottage at 137 DeKoven Street, in a dense West Side ward of wood cottages, sheds, and fences — after a rainless summer.

Sun · Oct 8~9:30 p.m.

The alarm goes wrong

A watchman misjudges the location and sends an alarm to the wrong district. Crews — already worn out from a large fire the night before — arrive late to a blaze the wind has taken hold of.

Sun · Oct 8~11:30 p.m.

Across the South Branch

Wind-borne embers vault the South Branch of the Chicago River, igniting the gasworks and the mills and setting the central business district alight.

Mon · Oct 9~1:30 a.m.

The courthouse falls

The domed county courthouse burns; its great bell crashes through the collapsing tower. Prisoners in the basement jail are released to flee.

Mon · Oct 9~3:00 a.m.

Into the North Side

The fire jumps the Main Branch of the river into the North Division. When the waterworks burns, the city’s pumps fail — and with them, any hope of fighting the flames.

Mon · Oct 9Daylong

The North Side consumed

Block after block of mansions and workers’ housing burns northward. Tens of thousands flee toward the lake and the open prairie, carrying what they can.

Tue · Oct 10Pre-dawn

Rain, and the end

A light rain begins as the fire reaches Fullerton Avenue — then the city limit — and burns itself out against prairie and lakeshore. The great fire is over.

Print of the burning Chicago skyline seen from the west side of the river, October 9, 1871 — **The great fire at Chicago, Oct. 9th 1871 — view from the west side.** Chromolithograph, Gibson & Co. · via Wikimedia Commons (public domain).

The Same Night

The deadlier fire that same night

Two hundred and fifty miles north, the same drought and the same dry wind did something far worse. On the very night Chicago caught, the lumber town of Peshtigo, Wisconsin, and the forests around it were swallowed by a firestorm that remains the deadliest wildfire in American history. It is far less remembered, and not only because Chicago burned the same night and took the wires. Peshtigo was a remote lumber town, and the records that would have counted its dead burned along with them — which is why its toll survives only as a range.

Chicago, Illinois

~300

dead · about 2,112 acres · remembered the world over, its name a byword for catastrophe and comeback.

Peshtigo & the north woods

1,200–2,400

dead across the region, of whom perhaps 500 to 800 died in Peshtigo itself — about half the town · roughly 1.2 million acres · the deadliest wildfire in U.S. history, and far less remembered.

Set the two tolls side by side and a question forms. How did Chicago lose a third of itself and perhaps three hundred lives, while a far smaller town lost something like half its people in a single evening? The difference is mostly pace and escape. Chicago burned for some thirty hours, travelling in one direction, with a lake at its back and open prairie beyond it — tens of thousands simply walked out ahead of the flames. Peshtigo was overrun in a night, in forest, by a fire that made its own wind. There was nowhere to walk to.

The two were not alone either. That same night, fires also tore through Michigan — Port Huron, Holland, Manistee. Historians group them as the Great Fires of 1871. So what lit half the upper Midwest on one evening? The shared date has fed a durable theory that fragments of a passing comet did it. The duller answer is the documented one: a single parched autumn and a single dry wind, working on a landscape that had been waiting all summer for a match.

The Comeback

The fire slowed Chicago’s growth. It did not stop it.

A third of Chicago was ash. It could have been the end, and it was not: the city counted about 299,000 people the year before the fire, over 500,000 by 1880, and more than a million by 1890. The tidy version of that story — the fire as the making of the city — does not survive the arithmetic below. Chicago did not grow because it burned.

Read the rates, not the bars. The columns climb, so the chart looks like a city accelerating. The percentages say something more interesting. Chicago added 167 percent in the 1860s, then 68 percent in the decade of the fire — its slowest stretch to that point — then 119 percent in the rebuilt 1880s. The fire did not make Chicago bigger. It failed to stop Chicago getting bigger, which is a different and more durable kind of claim.

The Myth & the Rebuilding

The unsolved cause, and the city rebuilt in stone

Nobody knows who started it

The famous cause was an invention. A reporter admitted decades later that he invented Mrs. O’Leary’s cow and its kicked lantern for a livelier story, and in 1997 the City Council formally exonerated her. Debunking the cow, though, did not solve the case. The fire began in or beside the O’Leary barn on DeKoven Street; who or what lit it has never been settled. Suspicion has since fallen on the neighbor who raised the first alarm and on young men said to have been gambling in the barn that night. The official cause remains unknown.

A city rebuilt in stone

Relief poured in from across the nation and the world. Within a generation Chicago rebuilt bigger and less flammable — new fire codes, brick and steel, and an architecture of ambition. The rebuilding boom set the stage for the steel-framed skyscraper and the 1893 World’s Columbian Exposition.

The fire is still here

More than 150 years on, this is not a story Chicago has to go looking for. Six pieces of it are in daily use.

You stand on it

Grant Park

The city dumped the burned rubble — lumber, broken glass, ruined furniture — into the lake east of Michigan Avenue, roughly between Randolph and Roosevelt. That landfill became Grant Park. Buckingham Fountain, Lollapalooza and the Bean all sit on the wreckage.

You carry it

The second star

Of the four red stars on the city flag, the second one is this fire. Wallace Rice’s original design had only two stars — the fire and the 1893 World’s Fair. It was one of just two events Chicago first chose to represent itself with.

You walk the scar

The Loop and beyond

The 2,112 acres that burned are now the Loop, River North, Streeterville and the Gold Coast — the densest and most valuable ground in the city. The burn district and the postcard are the same place.

The origin

137 DeKoven Street

The barn where it began. The site is now the Robert J. Quinn Fire Academy, built in 1961 — the city trains its firefighters on the spot where the fire started, marked by a bronze “Pillar of Fire.”

The survivor

The Old Water Tower

One of the few public buildings left standing in the burned district. It still stands on Michigan Avenue, a limestone landmark ringed by the towers of the city that grew up around it.

From the ashes

A library from abroad

The fire burned millions of books. England shipped some 8,000 to replace them — volumes signed by Queen Victoria, Darwin and Tennyson among them — and they became the founding collection of the Chicago Public Library.

“Chicago Shall Rise Again.”Rallying cry of the rebuilding, 1871

Sources & method. Toll figures follow standard histories (the Chicago History Museum’s Great Chicago Fire & the Web of Memory project) and are widely cited estimates, not exact counts; the death toll of roughly 300 is an official estimate long thought low, since many bodies were never recovered. Reputable sources genuinely disagree on several figures — damages are put at $200 million by most histories and $222 million by the National Weather Service, the burned area at 2,112 acres by most histories and 2,124 by the Weather Service, and the city’s 1871 population at somewhere between 300,000 and 334,000. Where sources conflict we print the range. The drought figures and fire-weather detail are from the National Weather Service’s reconstruction of October 1871; the fire department’s condition is from contemporary accounts. The unresolved cause and the named suspects are set out by Time. The Peshtigo fire is documented by the National Weather Service and History.com; the wider Great Fires of 1871 by standard histories. Population figures are from the U.S. Census (1860–1900). The origin site, Water Tower, and the library’s founding donation are documented by the City of Chicago and the Chicago Public Library. Grant Park’s origin as fire landfill is documented by WTTW and the Chicago Public Library; the flag’s second star is the city’s own published symbolism. The river, lakeshore, and city geography are drawn from real coordinates; the burn district is an approximate reconstruction from period survey maps.

Reported by KCM Desk from the National Weather Service’s reconstruction of October 1871 and the standard histories; published July 24, 2026. If you spot an error, corrections come first.