Lewis and Clark Expedition Begins

The Corps of Discovery departed Camp Dubois near present-day Hartford, Illinois, on May 14, 1804, under the command of Meriwether Lewis and William Clark. Commissioned by President Thomas Jefferson following the Louisiana Purchase, the expedition's objectives included mapping a route to the Pacific Ocean, documenting flora and fauna, and establishing diplomatic contact with Indigenous nations. The party of approximately 45 members traveled up the Missouri River, reaching the Pacific coast in November 1805 and returning to St. Louis in September 1806.