On August 19, the following notable historical events related to Missouri have been recorded:

• 1804: The Lewis and Clark Expedition was near present-day Sioux City, Iowa, across from Missouri’s Atchison County, on or around August 19. They continued documenting the region’s geography and prepared for a council with the Sioux tribes, advancing their exploration of the Louisiana Purchase.
• 1838: During the Mormon War in Missouri, tensions remained high. On or around August 19, non-Mormon vigilantes in Daviess and Carroll Counties intensified their campaign against Mormon settlers, with skirmishes escalating the conflict that led to the Mormon expulsion order later in 1838.
• 1861: During the Civil War, the aftermath of the Battle of Wilson’s Creek (August 10) was ongoing in Missouri. On August 19, Union forces were regrouping after their retreat from Springfield, while Confederate forces maintained their position in southwest Missouri, underscoring Missouri’s critical role in the conflict.
• 1873: The Missouri Pacific Railroad expanded its network through central Missouri around August 19, completing a key line connecting Jefferson City to other regions, boosting the state’s transportation and economic infrastructure.
• 1904: The St. Louis World’s Fair, or Louisiana Purchase Exposition, was ongoing, with August 19 featuring international trade exhibits and cultural performances, reinforcing Missouri’s prominence as a global hub.
• 1964: The St. Louis Cardinals played a notable game against the Chicago Cubs at Busch Stadium on August 19, with Ken Boyer hitting a game-winning home run, contributing to their World Series-winning season and reinforcing Missouri’s baseball legacy.