Clark brought his slave on the journey.

York statue by Ed Hamilton. (Credit: Dennis Macdonald/Getty Images) Along with more than two-dozen enlisted men and officers, the Corps of ...

The Spanish sent soldiers to arrest the expedition.

The Spanish sent soldiers to arrest the expedition. Jefferson often described Lewis and Clark’s expedition as a scientific mission to stu...

Thomas Jefferson believed the expedition might encounter wooly mammoths.

Woolly Mammoth. (Credit: Royal BC Museum, Victoria, British Columbia) Before Lewis and Clark completed their expedition, Americans could on...

Lewis had served as Thomas Jefferson’s secretary.

Lewis had served as Thomas Jefferson’s secretary. In 1801, Lewis left the army and accepted an invitation to serve as Thomas Jefferson’s ...

Lewis first met Clark after being court-martialed by the Army.

Lewis (L) and Clark (R). (Credit: Jean-Erick PASQUIER/Getty Images) While serving as a frontier army officer in 1795, a young Meriwether Le...

Lewis and Clark Expedition

In May 1804, President Thomas Jefferson dispatched Meriwether Lewis and William Clark’s Corps of Discovery on an expedition to explore the L...