1. The first Missouri State Fair was held on May 4, 1852, in Sedalia. The fair has since become an annual event and is one of the largest agricultural fairs in the United States.

2. In 1949, the Missouri General Assembly designated May 4th as "Missouri Arbor Day." This day is now celebrated annually across the state with tree planting and conservation events.

3. On May 4, 1970, a group of Kent State University students protesting the Vietnam War were shot and killed by National Guard troops. The event sparked protests across the country, including in Missouri.

4. In 2003, the Missouri Legislature designated May 4th as "Bird Day" in recognition of the state's diverse array of bird species. Missouri is home to over 400 different bird species, including the state bird, the eastern bluebird.

5. On May 4, 2007, the city of Joplin, Missouri, was hit by an EF5 tornado that killed 158 people and caused over $2 billion in damage. The tornado, one of the deadliest in US history, prompted a national response and a widespread outpouring of support for the devastated city.