1. In 1821, Missouri became the 24th state of the United States, after a long journey to gain statehood. This date, known as Missouri's Statehood Day, is celebrated annually in the state.

2. On August 17, 1861, Union troops under the command of General Nathaniel Lyon clashed with Confederate forces in the Battle of Wilson's Creek, near Springfield, Missouri. The battle was one of the first major engagements of the Civil War in the Western Theater.

3. The State Fair of Missouri, one of the largest agricultural fairs in the country, began on August 17, 1901. The fair, held annually in Sedalia, Missouri, features livestock exhibitions, carnival rides, live music, and other attractions.

4. In 1982, the first Missouri Lottery game was sold on August 17. The lottery has since become a major source of revenue for the state, funding education, health care, and other programs.

5. On August 17, 2009, Missouri Governor Jay Nixon declared a state of emergency in response to severe flooding throughout the state. The floods caused significant damage to homes, businesses, and infrastructure, and the state received federal disaster assistance to aid in recovery efforts.