Catherine O'Leary

[1] Due to a high wind and dry conditions, it spread to burn a large percentage of the city, an event known as the Great Chicago Fire.

[4] The official report simply states: "Whether it originated from a spark blown from a chimney on that windy night, or was set on fire by human agency, we are unable to determine".

[3] Other rumors insisted that Daniel Sullivan had started the fire, or that perhaps it was Louis M. Cohn, who claimed to have been gambling in the barn with the O'Learys' son and others.

In the PBS documentary Chicago: City of the Century, a descendant of O'Leary's stated that she spent the rest of her life in the public eye, and she constantly was blamed for starting the fire.

[6] Amateur historian Richard Bales gathered sufficient evidence on Sullivan to convince the Chicago City Council to exonerate O'Leary of any guilt in 1997.