The fire killed more than 250 people, left 100,000 homeless, destroyed more than 17,400 structures and burned more than 2,000 acres.
According to popular legend, the fire broke out after a cow - belonging to Mrs. Catherine O'Leary - kicked over a lamp, setting first the barn, located on the property of Patrick and Catherine O’Leary at 137 Dekoven Street on the city’s southwest side, then the whole city on fire. Chances are you've heard some version of this story yourself; people have been blaming the Great Chicago Fire on the cow and Mrs. O'Leary, for more than 130 years. Mrs. O’Leary denied this charge. Recent research by Chicago historian Robert Cromie has helped to debunk this version of events.
Like any good story, the 'case of the cow' has some truth to it. The great fire almost certainly started near the barn where Mrs. O'Leary kept her five milking cows. But there is no proof that O'Leary was in the barn when the fire broke out - or that a jumpy cow sparked the blaze. Mrs. O'Leary herself swore that she'd been in bed early that night, and that the cows were also tucked in for the evening.
After the Great Fire, Chicago Tribune reporter Michael Ahern published a report that the fire had started when a cow kicked over a lantern while it was being milked. The woman was not named, but Catherine O'Leary was identified. Illustrations and caricatures soon appeared depicting Mrs. O'Leary with the cow.
In 1893, however, Ahern admitted he had made the story up.
"Mrs. O'Leary's cow" has attracted the attention and imagination of generations as the cause of the fire. Numerous references, in a variety of media, have been made in American popular culture, including films, television, and popular music.
But if a cow wasn't to blame for the huge fire, what was? Over the years, journalists and historians have offered plenty of theories. Some blamed the blaze on a couple of neighborhood boys who were near the barn sneaking cigarettes. Others believed that a neighbor of the O'Leary's may have started the fire. Some people have speculated that a fiery meteorite may have fallen to earth on October 8, starting several fires that day - in Michigan and Wisconsin, as well as in Chicago.
The Peshtigo Fire, the most devastating forest fire in American history, was the biggest blaze that week, but drew little note outside of the region–in and around Peshtigo, Wisconsin– because of the attention drawn by the Great Chicago Fire.
The Peshtigo Fire, which also occurred on October 8th, 1871, roared through Northeast Wisconsin, burning down 16 towns, killing 1,152 people, and scorching 1.2 million acres before it ended.
Historical accounts of the fire say that the blaze began when several railroad workers clearing land for tracks unintentionally started a brush fire. Before long, the fast-moving flames were whipping through the area 'like a tornado,' some survivors said. It was the small town of Peshtigo, Wisconsin, that suffered the worst damage. Within an hour, the entire town had been destroyed.
Those who survived the Chicago and Peshtigo fires never forgot what they'd been through; both blazes produced countless tales of bravery and heroism. But the fires also changed the way that firefighters and public officials thought about fire safety. On the 40th anniversary of the Great Chicago Fire, the Fire Marshals Association of North America (today known as the International Fire Marshals Association), decided that the anniversary of the Great Chicago Fire should henceforth be observed not with festivities, but in a way that would keep the public informed about the importance of fire prevention. The commemoration grew incrementally official over the years.
In 1920, President Woodrow Wilson issued the first National Fire Prevention Day proclamation, and since 1922, Fire Prevention Week has been observed on the Sunday through Saturday period in which October 9 falls. The President of the United States has signed a proclamation proclaiming a national observance during that week every year since 1925.