1. On February 20, 1792, the Illinois Territory was created by an act of Congress. It included parts of present-day Illinois, Wisconsin, and Michigan, and was established to govern the area prior to statehood.

2. In 1837, on February 20th, the City of Chicago was incorporated. It had previously been a small trading post and frontier settlement, but its incorporation marked the beginning of its rapid growth into a major transportation hub and commercial center.

3. The infamous Chicago Haymarket Riot occurred on May 4, 1886, but it was on February 20, 1887, that four of the accused anarchists were hanged in Chicago's Cook County Jail. The event was highly controversial at the time and continues to be remembered as a significant moment in labor history.

4. February 20, 1962, marked the opening of O'Hare International Airport in Chicago. It quickly became one of the busiest airports in the world and an important hub for domestic and international travel.

5. On February 20, 2003, the tragic Station Nightclub fire occurred in West Warwick, Rhode Island. Although the incident did not happen in Illinois, it had a major impact on the state. Many of the victims were from Illinois, and the tragedy led to stricter regulations and safety standards for entertainment venues across the country.