She was perhaps the greatest “scapecow” in history. We don’t know if her name was Daisy, Madeline, or Gwendolyn (each name has been suggested), but Mrs. O’Leary’s cow was blamed for the 1871 Great Chicago Fire that left every third resident of the city homeless. Carried by strong winds through wooden structures, the fire burned for three days and took the lives of nearly 300 people.

For years, many believed the fire began when the cow knocked over a lantern left burning in a shed. After further investigation—126 years later—the city’s Committee on Police and Fire passed a resolution exonerating the…