Mrs. O’Leary’s Cow Didn’t Start Any Fires

“A spark neglected has often raised a conflagration.” —Quintus Curtius Rufus

In A Nutshell

The Great Chicago Fire of 1871 was responsible for over 100 deaths and millions of dollars in damage. It became known as one of the largest disasters in US history, and even more incredible was the fact that such an enormous disaster was caused by a lone cow kicking over a lantern . . . except it wasn’t. As it turns out, no one knows for sure who started the blaze, and an unscrupulous reporter simply invented the cow story for the sake of an eye-catching headline.

The Whole Bushel

Mrs. Catherine O’Leary’s cow often gets blamed for starting the Great Chicago Fire of October 8, 1871. According to legend, the woman was out milking her cow when it accidentally kicked over a lantern and started the inferno that took out the whole city. Indeed her barn was the first building to be consumed by the fire, but there’s no evidence the cow or Mrs. O’Leary was involved in any way. In fact, the origins of the conflagration remain somewhat of a mystery, although there is no shortage of theories.

If we’re to believe the confession of Chicago Republican reporter Michael Ahern, he started the myth of the cow as a way to boost intrigue and sell newspapers. Apparently, other newspapers ran with Ahern’s story and even began theorizing O’Leary may have started the fire on purpose in an effort to seek revenge on the city that cut off her welfare money for not reporting the profits from her milk sales. Thus, the O’Leary conspiracy began. Did she start the fire on purpose, or did the cow accidentally knock over the lamp? No one was certain, yet the media pegged the woman and her cow as the prime suspects.

Mrs. O’Leary claimed she and her entire family were asleep at the time of the fire, and she never went into the barn at night (she milked her cows in the day, like most people). In addition, the authority’s official report could not pinpoint the cause of the blaze and they certainly didn’t name the O’Learys as the instigators.

Article Continued Below

With such obvious holes in the cow story, other theories have surfaced. Some point the finger at “Peg Leg” Sullivan who admitted he was outside the O’Leary’s property smoking a pipe at the start of the fire. There are those who think he didn’t just spot the flames but caused them. Others believe different neighbors, the McLaughlins, were the culprits, since they were supposedly seen going into the barn that night to get some milk for their dinner party. However, Mrs. McLaughlin claimed no one in her family went into the barn, and she didn’t serve anything at her party that required milk. Other hypotheses for the cause of ignition range from boys sneaking into the barn for a smoke to pieces of Biela’s Comet falling on the property. Also, in the 1940s, Louis M. Cohn posthumously confessed to starting the fire (but again, there was no proof).

With so many different stories, confessions, and people in the vicinity of the barn at the time in question, we’ll likely never know what started the fire that cost the Windy City over $200 million in property damage, killed more than 100, and left 100,000 homeless. But considering the conditions at the time, it seems even the tiniest spark could have sent Chicago up in smoke. After all, it was a particularly dry summer, the winds were high, and the city was built almost entirely with wood.

Show Me The Proof

Chicago History: The O’Leary Legend
Did the Great Chicago Fire really start with Mrs. O’Leary’s cow?
The Great Chicago Fire

Looking for our newsletter? Subscribe here!