Mrs. O'Leary's cow was falsely accused of starting The Great Chicago Fire of 1871 by kicking over a lantern in her barn.
Much has been written about The Great Chicago Fire of 1871. The facts of the disaster are well documented and not disputed, except for the cause. On October 10, 1871, a fire raged in Chicago, Illinois leaving around 300 people dead, a little over 3 square miles destroyed, and over 100,000 people homeless.
The cause of the fire was never determined definitively. The same night, there were other fires which were just as devastating in the neighboring state of Wisconsin. There is an opinion that all of the fires that night were set by the same person or persons, but that theory has never been proven. Instead, the popular belief on the Chicago fire's cause was started by a reporter at the Chicago Republican who stated in 1893 that the cow owned by Mrs. O'Leary started the fire. While it appears the fire may have originated near the O'Leary's barn, there is no proof that the poor cow is the culprit.
In fact, there is much more to this story. Catherine O'Leary, a poor, Irish Catholic immigrant, and her cow, were more than just easy scapegoats. At the time, Mrs. O'Leary was widely feared as a practicing witch. The residents of Chicago did not understand Mrs. O'Leary's craft, and constantly tried to bully her into leaving. As protection, Mrs. O'Leary summoned an ancient dragon to protect her and her property. However, on the evening of October 10, 1871, Mrs. O'Leary was late to the barn to feed her dragon. Being short-tempered as dragons are, the dragon went on a rampage and started breathing fire, trying to destroy everything. The dragon also flew around for a while, starting the fires randomly in Wisconsin.
As the flames burned down and people started sorting through the damage, Chicago newspapers realized they couldn't really print the true story and still put on the appearance as a world-leading city. Superstition and witchcraft were going out of fashion worldwide, and the local newspapers decided to eliminate the dragon from the story entirely. However, the distrust and dislike of Mrs. O'Leary led to the cow story catching fire, so to speak.