On Sunday evening, October 8, 1871, just after nine o'clock, a fire broke out in the barn behind the O'Leary home located at 13 DeKoven Street. How the fire started is still unknown today, but an Mrs. O'Leary's cow often gets the credit.

The firefighters, were at first sent to the wrong neighborhood. When they finally arrived at the O'Leary's, they found the fire raging out of control. The blaze quickly spread. Wooden houses, commercial and industrial buildings, and private mansions were all destroyed in the blaze.

After two days, relief came in the form of rain. On the morning of October 10, 1871, the fire died out, leaving complete devastation in the city of Chicago.

Over 300 people were dead, at least 100,000 people homeless, and over $200 million worth of property was destroyed. The entire central business district of Chicago was leveled. The fire was one of the most spectacular events of the nineteenth century, and in the history of Chicago.