The Great Chicago Fire began around 9:00 PM on Sunday, 8 October, 1871, on an alley behind 137 Dekoven Street in Chicago, Illinois and burned until Tuesday, 10 October, 1871. Initially, it was believed that the fire was started when a cow kicked over a lantern in a shed belonging to Patrick and Catherine O’Leary. In 1893, Michael Ahern, the Chicago Republican reporter who circulated this story, admitted that it was false.
Several factors helped the fire spread. The area had been suffering a severe drought. Strong winds contributed to the spread of the blaze. The city of Chicago had relied heavily on wood as a building material, and had even constructed elevated roads and sidewalks out of wood planks. The fire fed on wooden frame houses, which had been constructed very close together, and firewood stored inside of buildings. The fire also fed on the city’s shipyards and on the commercial coal and lumber yards along the river. Strong winds and intense heat meant that the fire was soon too large to contain; when the fire destroyed the city’s waterworks, firefighters had to give up.
The Great Chicago Fire burned itself out, assisted by a light rain that began falling on the night of Monday, 9 October, 1871.