1. On May 12, 1820, Missouri was admitted as the 24th state in the United States, becoming the first state to be created entirely from the Louisiana Purchase.

2. In 1937, the Missouri River Flood caused widespread destruction in Kansas, Nebraska, Iowa, and Missouri. The devastating flood lasted several weeks and resulted in over 100 people losing their lives.

3. On May 12, 1954, the U.S. Supreme Court issued its landmark decision in the case of Brown v. Board of Education, declaring racial segregation in public schools to be unconstitutional. The case originated in Topeka, Kansas but had a significant impact on Missouri and the rest of the United States.

4. In 2008, the Missouri State Capitol was damaged by a powerful tornado that swept through the city of Jefferson City. The tornado caused extensive damage to the Capitol dome, but no one was injured in the storm.

5. On May 12, 2012, a deadly bus crash occurred near Carrollton, Missouri. A charter bus carrying a group of Vietnamese-American Catholics collided with a tractor-trailer, resulting in 4 deaths and over 50 injuries. The crash is considered one of the deadliest in Missouri's history.