1. The Missouri Compromise was signed on June 4, 1820, admitting Missouri as a slave state and Maine as a free state. The compromise also established a boundary line at 36°30'N latitude, where slavery was prohibited in all new states north of the line.
2. On June 4, 1940, the first water was released from Bagnell Dam, creating the Lake of the Ozarks, a popular tourist destination in Missouri. The lake covers 54,000 acres and has 1,150 miles of shoreline.
3. Missouri Statehood Day is celebrated on June 4 every year to commemorate the day Missouri was admitted as a state to the United States in 1821. Missouri is known as the "Show-Me State" and is home to the Gateway Arch, the tallest national monument in the US.
4. On June 4, 1919, the Missouri state legislature ratified the 19th Amendment to the US Constitution, which gave women the right to vote. Missouri was the 11th state to ratify the amendment, and it was officially adopted on August 26, 1920.
5. In 2009, Missouri became the first US state to enact a law that prohibits drivers under 21 from sending text messages while driving. The law, known as "Katie's Law," is named after Katie Gray, a teenager who was killed in a car accident while texting and driving. The law also bans drivers of all ages from sending or reading text messages while driving in school zones.