8 Unexpected Truths About the Great Chicago Fire of 1871—150 Years Later

On October 8, 1871, Chicago was engulfed in a devastating blaze. For two days, the fire raged uncontrollably as firefighters battled to contain it. A sudden rainstorm eventually helped douse the flames, but not before 300 lives were lost, 100,000 were left homeless, and damages totaling $200 million—equivalent to nearly $4.5 billion today—were incurred.

Like a phoenix, Chicago emerged from the ashes. Today, 150 years later, the city shines brightly along Lake Michigan’s shores, a symbol of its people’s enduring strength. To dispel myths and uncover truths, here are some lesser-known facts about the Great Chicago Fire of 1871.

1. Contrary to popular belief, Mrs. O’Leary did not cause the Great Chicago Fire of 1871. (Her cow is also innocent.)

Although many think the fire started when Mrs. O’Leary’s cow tipped over a lantern, the blame placed on Mrs. O’Leary likely stemmed from xenophobia, misogyny, anti-Catholic bias, and classism. Joseph Medill, co-owner of the Chicago Tribune, frequently published anti-Irish articles. Joseph Edgar Chamberlain of the Chicago Evening Post openly stated that “that neighborhood” where the fire originated “was unfamiliar to respectable Chicagoans.” In reality, the fire’s cause remains unknown, and Mrs. O’Leary and her cow were cleared of all charges in 1997.

2. Fire tornados were part of the disaster.

Referred to as fire whirls or convection whirls, the intense heat colliding with cooler air created spinning flames that one witness described as “roaring like countless evil spirits.” These fiery whirls could form walls of flame towering up to 100 feet, transforming the city into a living nightmare.

3. The Great Chicago Fire wasn’t the most devastating fire in the Midwest that month.

While Chicago was engulfed in flames, the Peshtigo Fire was devastating Wisconsin, located just north along Lake Michigan. Fueled by similar conditions, the Peshtigo Fire was even more extensive, destroying an area 10 miles wide and 40 miles long. It was also more deadly, claiming around 1,500 lives.

4. Chicago’s rapid destruction was due to its predominantly wooden structures.

Though modern cities are known for concrete and steel, 19th-century Chicago was largely constructed from timber sourced from Wisconsin’s forests. Even roads and sidewalks were made of wooden planks, which turned into deadly fire traps, hindering escape.

William Ogden, Chicago’s first mayor from 1837 to 1838, played a key role in developing the region’s timber industry. As noted by the Peshtigo Fire Museum, Ogden “set up a barge line between Peshtigo Harbor and Chicago” and later expanded into railroads to transport lumber more efficiently. Ogden, who also owned a lumber company in Peshtigo, lost nearly all his personal and business assets in the two fires.

5. The Great Fire spurred the gentrification of Chicago.

While many believe the fire spurred Chicago’s rise as a skyscraper hub, the skyscraper boom didn’t begin until a decade later. However, working-class residents still faced gentrification challenges. As Jerry Larson, a professor emeritus of architecture at the University of Cincinnati explained to WTTW, “most structures were rebuilt to resemble their pre-fire appearance.” Using non-wood materials was too expensive, pushing working-class Chicagoans who couldn’t afford fire-resistant options out of the downtown area.

6. Not all of Chicago was destroyed.

Though many imagine Chicago as completely ruined, the reality is less dramatic. While the downtown business district was devastated, much of the West Side survived. Importantly, the South Side stockyards, most railroads, and the wharfs, mills, and lumberyards along the Chicago River were left unharmed, enabling the city and its economy to recover quickly and maintain its role as the “hog butcher of the world.”

7. The Great Chicago Fire provides insights for addressing climate change.

Many are unaware of how exceptionally dry Chicago was in the summer and fall of 1871. WGN meteorologist Tom Skilling notes that “the last substantial rainfall before the fire was 1.57 inches on July 3,” making the period from Independence Day to the fire the driest in Chicago’s history. With rising global temperatures and more frequent droughts causing wildfires, the conditions that fueled the Great Chicago Fire could provide valuable insights into our evolving climate.

8. An Oscar-winning movie was inspired by the Great Chicago Fire.

Over six decades after the fire, a film dramatizing the disaster won an Oscar. Released in 1938, In Old Chicago offers a fictionalized account of the events leading to the blaze, focusing on Dion O’Leary, Mrs. O’Leary’s son, portrayed by Tyrone Power. Despite taking creative liberties with characters and events, the film received six Academy Award nominations, with Alice Brady winning Best Supporting Actress for her role as Mrs. O’Leary.