The world’s most infamous clown, John Wayne Gacy, went on trial after he murdered 33 young men in Cook County, Illinois.
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Great Chicago Fire begins.
The FDA approved the first oral contraceptive pill called Enovid.
The Cherry Mine disaster in Illinois killed 259 miners in a coal mine fire.
The first Dairy Queen restaurant opened in Joliet, Illinois, US.
Illinois became the first US state to make it compulsory by law to wear a seatbelt.