On May 14, 1804, President Thomas Jefferson’s private secretary, Meriwether Lewis, and an army captain, William Clark, began an expedition exploring the territory stretching from the Mississippi River, along the Missouri River, all the way to the Pacific Ocean. But the origins of the expedition began long before this, even before Jefferson became president of the United States and well before the Louisiana Purchase took place. Only a few years after the Revolutionary War, shortly after sea captain Robert Gray had discovered the estuary of the Columbia River in present-day Oregon, Jefferson instructed Andre Michaux to “explore the country a[long] the Missouri, & thence Westwardly to the Pacific ocean.”  The enterprise was sponsored by the American Philosophical Society and included the support of subscribers such as George Washington and Benjamin Franklin. The expedition was quickly ended before the entourage reached the Missouri River after it was discovered that Michaux was acting as an agent of the French government. Other expeditions, led by explorers such as Zebulon Montgomery Pike, Thomas Freeman, William Dunbar, and Peter Custis, were also enlisted by Jefferson during his presidency to explore various sections of the American West, but none of these luminaries have gained the popular recognition that the Lewis and Clark Expedition retains today.
Meriwether Lewis, like Jefferson, was born into a family of Virginia planters. Lewis served for a time in the army during the Whiskey Rebellion, but saw no combat. For a period of about six months, Lewis served under the command of William Clark, who was the younger brother of the Revolutionary War commander, George Rogers Clark. Lewis left the army as a captain to become the private secretary to President Jefferson, whom he advised on the capabilities and political loyalties of high-ranking officers in the military. Lewis availed himself of Jefferson’s personal library, which was considered one of the finest in the world. After his appointment as the commander of the expedition to the west (also known as the “Corps of Discovery”) Lewis received instruction in astronomy, botany, and medicine by some of the leading scientists in the country to prepare him for his mission. Lewis later asked William Clark to join in the command with the rank of captain, although the initial budget for the expedition included pay for only one captain. Clark was eventually commissioned as a lieutenant, although this was not known to the crew.
President Jefferson first proposed the Lewis and Clark expedition in a secret message to Congress on January 18, 1803, months before the Louisiana Purchase took place. The message stressed the need for the government to develop the fur trade along the Missouri River in what was then Spanish territory. Jefferson wished to provide new lands to compensate private fur traders who would be forced out as the federal government purchased Indian titles to land along the Mississippi River. Jefferson hoped to induce Native-American tribes to take up agriculture and abandon their reliance upon hunting and fur-trading. Although the primary purpose of the expedition was commercial in nature, it should be understood that with that commercial development, significant expansion in government authority would necessarily take place. In addition to its implications for commerce and government, the expedition had other purposes and objectives. Jefferson’s specific marching orders to Lewis indicated that “the object of your mission is to explore the Missouri river, & such principal stream of it, as, by its course and communication with the waters of the Pacific ocean, whether the Columbia, Oregan, Colorado or any other river may offer the most direct & practicable water communication across this continent for the purposes of commerce. . . . Beginning at the mouth of the Missouri, you will take [careful] observations of latitude & longitude, at all remarkeable points on the river, & especially at the mouths of rivers, at rapids, at islands, & other places & objects distinguished by such natural marks & characters of a durable kind, as that they may with certainty be recognised hereafter….The interesting points of the portage between the heads of the Missouri, & of the water offering the best communication with the Pacific ocean, should also be fixed by observation, & the course of that water to the ocean, in the same manner as that of the Missouri.”
Jefferson clearly had interest in the geographic and scientific discoveries that the expedition could make, and was particularly interested in learning if a water route from the Missouri to the Pacific could be found. Jefferson also hoped to learn something about the life of the Native American tribes the expedition would encounter along the way.
The original plan was for Lewis to lead a party of only a dozen or so men. A larger party was thought to be perceived as a military threat to the Native Americans encountered along the way. Lewis and Clark, however, decided to add some additional members for the expedition, while still keeping the numbers down to a sufficiently small size to convince the Indians of their peaceful intentions. The expedition departed from the northern bank of the Missouri River, just north of St. Charles, Missouri, on May 21, 1804. Traveling in a heavily laden keelboat and two pirogues, the expedition only traveled three-and-a-half miles before stopping to camp for the night. Twenty-eight months later, the expedition returned to St. Louis. A total of forty-five men began the expedition. Others were added for a while on the journey but left before the expedition was completed. Thirty-three returned. One member died along the way of a “bilious colic,” which may have been appendicitis. The party included William Clark’s African-American slave, York, and a French-Canadian fur trader Toussaint Charbonneau, and his Shoshone wife, Sacagawea, who was pregnant when she joined the expedition. Sacagawea was a talented interpreter of Indian languages, and also skilled in finding edible plants on the westward journey. Her very presence in the party was beneficial in that Native American tribes did not believe a war party would contain a woman in its midst. This provided convincing evidence that the Corps of Discovery had peaceful intentions. Throughout the entire expedition, the party had only one lethal encounter with Native Americans. A band of Piegan Blackfeet Indians attacked the camp in an attempt to steal horses and weapons. Two of the Blackfeet were killed in the battle.
The Corps of Discovery made slow progress up the Missouri River and into the Rocky Mountains. The expedition had to proceed on foot and on horseback for much of the way after learning that there was no water route through the mountains to the ocean. The expedition made its way to the Pacific coast by the December of 1805, when it voted to spend the winter at Fort Clatsop. The entire party participated in the decision, including York and Sacagawea, perhaps marking the first time that an African-American slave and a Native American woman had participated formally in a decision of a federal governmental body.
Lewis and Clark made their return in the spring of 1806. In July, Lewis took part of the company with him while Clark took the remainder to explore different paths within the territory of present-day Montana. The two groups re-joined one another in August in present-day North Dakota. The expedition proceeded back to St. Louis, where the party arrived on September 22. As Lewis scrambled out of his canoe, the first question that he had for a local resident was “When does the post leave?” Lewis was desperate to report to the president.
Lewis had been directed by Jefferson to keep a journal of his discoveries. Clark also kept a journal, which he filled with descriptions of his observations, as well as fine illustrations of flora and fauna above, beneath, and beside his handwritten text on the pages of the journal. Lewis traveled to Washington, D.C., to report directly to the president. What was said at that meeting is unknown, but it is clear that Lewis pledged to write and publish a book that would report his findings. Unfortunately, the book was never written. Jefferson offered Lewis an appointment as the governor of the territory of Louisiana. Jefferson no doubt expected that the position would provide income and security for Lewis as he authored his book. However, the sedentary position did not suit Lewis, who seemed unable to master administrative duties once the expedition was completed. He suffered from serious drinking problems, indebtedness, and acute melancholy. He died from gunshot wounds, probably by his own hand, while staying at an inn on a trip to Washington.
Because of Lewis’s death and failure to complete his narrative about the expedition, much of the scientific, ethnographic, and geographic findings of the enterprise were not fully appreciated. Many of the discoveries of plants and animals that the Corps made were, for a time, lost. Those species were later re-discovered many years later. Sergeant Patrick Gass, a member of the expedition, did compose a book length narrative about the venture, but that volume did not contain much of the kind of discoveries that were of original interest to President Jefferson. Francis Biddle, later the president of the Second Bank of the United States, conducted an “audit” of the enterprise and then was the primary, but uncredited author of the official history of the expedition, which appeared in two volumes. The second of the two volumes was devoted to the botanical and zoological discoveries of Lewis and Clark, but Biddle was neither an expert scientist nor a first-hand observer of the phenomena that he was to describe. Biddle was one of the great intellectuals of his age, but he was not scientifically trained and he could have benefited greatly from the elaboration that Lewis could have offered him had he lived. For these reasons, the significance of the expedition was not recognized in the first century after the return of the Corps of Discovery as it could have been and, in fact, as it has been in more recent years as more and more scholars have slowly uncovered more evidence of the events that took place. Today, we can see that the Corps of Discovery accomplished much in the way of learning of the terrain, climate, and physical environment of the trans-Mississippi West. The expedition learned much of the Native Americans who lived in that territory. This knowledge aided in the settlement and development of a massive land area on the North American continent. Obviously, those developments have had diverse implications for all involved, most notably for the Native Americans who lived there. Nevertheless, the Lewis and Clark expedition paved the way for the future transformation of much of what is now the United States.
James C. Clinger is a professor in the Department of Political Science and Sociology at Murray State University. He is the co-author of Institutional Constraint and Policy Choice: An Exploration of Local Governance and co-editor of Kentucky Government, Politics, and Policy. Dr. Clinger is the chair of the Murray-Calloway County Transit Authority Board, a past president of the Kentucky Political Science Association, and a former firefighter for the Falmouth Volunteer Fire Department.
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 Ambrose, Stephen E. 1996. Undaunted Courage: Meriwether Lewis, Thomas Jefferson, and the Opening of the American West. New York: Simon & Schuster. Pages 133-136.
 Guinness, Ralph B. 1933. “Purpose of the Lewis and Clark Expedition.” Mississippi Valley Historical Review 20 (January): 90–100.
 Ronda, James P. 1991. ‘A Knowledge of Distant Parts’: The Shaping of the Lewis and Clark Expedition. Montana: The Magazine of Western History, Vol. 41, No. 4 (Autumn): 4-19.
 Ambrose, Stephen E. 1996. Undaunted Courage: Meriwether Lewis, Thomas Jefferson, and the Opening of the American West. New York: Simon & Schuster. Pages 313-316.
 Ambrose, op cit. Chapter 32.
Ambrose, op cit. Chapter 39
 Snow, Spencer. 2013. “Maps and Myths: Consuming Lewis and Clark in the Early Republic.” Early American Literature 48 (3): 671–708.