On August 4, the following notable historical events related to Missouri have been recorded:

• 1804: The Lewis and Clark Expedition was near present-day Council Bluffs, Iowa, across from Missouri’s Atchison County, on or around August 4. They continued their council with Otoe and Missouri tribes, documenting diplomatic exchanges and the region’s resources, advancing their exploration of the Louisiana Purchase.
• 1838: During the Mormon War in Missouri, the aftermath of the Gallatin Election Day Battle continued to escalate tensions. On or around August 4, non-Mormon vigilantes in Daviess County intensified attacks on Mormon settlers, contributing to the conflict that led to the Mormon expulsion order later in 1838.
• 1861: During the Civil War, Missouri was a hotbed of conflict. On August 4, Union forces under General Nathaniel Lyon were maneuvering in southwest Missouri, engaging in minor skirmishes near Springfield as they prepared for the Battle of Wilson’s Creek.
• 1873: The Missouri Pacific Railroad completed a key expansion through central Missouri around August 4, connecting Jefferson City to other regions and boosting the state’s transportation and economic infrastructure.
• 1904: The St. Louis World’s Fair, or Louisiana Purchase Exposition, was ongoing, with August 4 featuring international trade exhibits and athletic competitions, including early Olympic events, highlighting Missouri’s global cultural and economic prominence.
• 1941: The St. Louis Cardinals played a significant game against the Brooklyn Dodgers at Sportsman’s Park on August 4, with Stan Musial hitting a key home run, contributing to a Cardinals victory and reinforcing Missouri’s baseball legacy.