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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Coopers Inc. started selling the world's first men's briefs in Chicago.
Illinois became the first US state to make it compulsory by law to wear a seatbelt.
Prolific killer John Wayne Gacy was given the death sentence for the murder of 33 young men and boys.
An F5 max rating tornado smashed through Plainfield, Illinois, killing 29 people, injuring 353, and causing $165 million in damages.
The first Dairy Queen restaurant opened in Joliet, Illinois, US.