On June 12, the following notable historical events related to Missouri have been recorded:
- 1804: The Lewis and Clark Expedition was in the St. Louis area on or around June 12, finalizing preparations for their journey up the Missouri River to explore the Louisiana Purchase. They were securing boats and supplies, reinforcing Missouri’s role as the starting point for western exploration.
- 1820: Missouri’s constitutional convention, convened in St. Louis, was actively drafting the state’s first constitution around June 12. This was a critical step toward Missouri’s admission as a state in 1821, amidst national debates over slavery tied to the Missouri Compromise.
- 1861: During the Civil War, Missouri saw escalating tensions. On June 12, following the failed St. Louis Conference the previous day, Union General Nathaniel Lyon began mobilizing forces to capture Jefferson City, a key move to secure Missouri for the Union against Confederate sympathizers.
- 1873: The Missouri, Kansas, and Texas Railway (Katy Railroad) began expanding its network through southwest Missouri around June 12, connecting Springfield to other regions and fostering economic growth in the state.
- 1904: The St. Louis World’s Fair, or Louisiana Purchase Exposition, was underway, with June 12 featuring early international trade exhibits and cultural displays, highlighting Missouri’s prominence as a global hub.
- 1967: The St. Louis Cardinals played a significant game against the Philadelphia Phillies at Busch Stadium on June 12, with Bob Gibson pitching a complete game and Roger Maris hitting a key home run, contributing to their World Series-winning season and reinforcing Missouri’s baseball legacy.