Little Known Facts - 5

“Meriwether Lewis’s Not-So-Secret Mission”

By the time President Thomas Jefferson returned to Washington, D.C. in 1802 from his customary summer respite at Monticello he had decided to include a proposal in his annual message to Congress to send a small exploratory expedition across the continent in search of an “all-water” route to the Pacific coast (in short, in search of the fabled Northwest Passage). When he circulated the draft message among members of his Cabinet, Secretary of the Treasury Albert Gallatin recommended the proposal for western exploration be the subject of a separate confidential message “as it contemplates an expedition out of our own territory.”

Jefferson took Gallatin’s advice. On January 18, 1803, in a secret message to Congress he requested an “appropriation of two thousand five hundred dollars ‘for the purpose of extending the external commerce of the U.S.’ while understood by the Executive as giving the legislative sanction, would cover the undertaking from notice, and prevent the obstructions which interested individuals might otherwise previously prepare in it’s way.” (Italics added.) Congress complied with the president’s request and approved the appropriation.

Thus, in a manner of speaking, the venture that was to become known as the Lewis and Clark Expedition was conceived and authorized in secrecy. In reality, from the outset it was known not only by the president and his personal secretary, Meriwether Lewis, but also by all members of his Cabinet and all members of both houses of Congress. As a matter of fact, this “state secret” became known to an ever-widening circle of confidants even as Jefferson and his chosen commander insisted on maintaining the fiction of strict confidentiality.

In December of 1802, President Jefferson had confided his plan (even before his secret message to Congress) to the Spanish ambassador to the U.S., Sr. Carlos Martinez de Yrujo, when he sought an official passport authorizing the explorers to cross Spain’s trans-Mississippi territories to the Pacific coast. Ever cautious, Ambassador Martinez de Yrujo declined Jefferson’s request and promptly reported the overture to his superiors in Madrid. Rebuffed, but undaunted, Jefferson subsequently made similar requests of the British and French ambassadors, both of whom were more obliging.

After the president appointed Meriwether Lewis to head the expedition, he enlisted the assistance of four of the nation’s leading natural scientists, all personal friends of his who were with the American Philosophical Society in Philadelphia, to tutor Lewis in such subjects as botany, biology, medicine and celestial navigation. He implored each of them to hold the pending expedition in “strictest confidence.” Hence, the circle of those sharing the “state secret” widened accordingly.

Still later, Lewis and Jefferson decided it would be prudent to recruit a second commanding officer in case some mishap befell Lewis while en route. In an extraordinary letter detailing the particulars of the mission, Lewis invited his former commanding officer, William Clark of Kentucky (and the Indiana Territory), to join him on equal terms to lead the endeavor. True to form, Lewis asked Clark to hold the information conveyed to him in complete confidence. Upon his acceptance of Lewis’s invitation, Clark was commissioned to recruit some vigorous, young, unmarried men possessing hunting skills and considerable capacity for hard work to join in the enterprise. As he did so, Clark at Lewis’s suggestion initially used a cover story alleging the purpose of the expedition was to ascend the Mississippi River and locate its headwaters. That subterfuge was maintained until just before the expedition pushed off up the Missouri River from its winter quarters at Camp River Dubois on May 14, 1804.

Clearly, Meriwether Lewis’s “hush-hush” mission was an open secret long before members of the expedition set foot in Spain’s former Louisiana Territory.

Dr. H. Carl Camp


Stephen E. Ambrose, Undaunted Courage: Meriwether Lewis, Thomas Jefferson, and the Opening of the West (New York: Simon & Schuster, 1996), pp. 77-100.

Donald Jackson, ed., Letters of the Lewis and Clark Expedition, with Related Documents, 1783-1854 (Urbana: University of Illinois Press, 1978), vol. 1, various letters and documents, pp. 2-41.

Last updated: December 13, 2016

Contact the Park

Mailing Address:

601 Riverfront Dr.
Omaha, NE 68102


(402) 661-1804

Contact Us