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Collection Louisiana: European Explorations and the Louisiana Purchase

The Exploration and Legacy of the Louisiana Territory

American Exploration of Louisiana

Acquisition and exploration of American lands throughout the first decade of the 19th century began and ended with President Thomas Jefferson. Whether involved in purchasing the Louisiana Territory; promoting national interests or nurturing his own curiosity by obtaining scientific, cultural, and geographic knowledge; or, organizing expeditions by choosing their leaders; planning their goals; and raising public and private funds for their execution; Jefferson stood at the forefront of those programs. Behind his involvement lay a firmly-rooted vision of an "empire of liberty" that stretched from the Atlantic to the Pacific coast.

Before 1800

In the decade following the American Revolution the federal government sponsored four attempts to explore the region beyond the Mississippi River. Jefferson prompted three of them and he was also involved in developing legislation for governing the admission of new territories to the United States. Rumors of a British expedition from the Mississippi Valley to California prompted Jefferson in late 1783 to tap revolutionary war hero and longtime friend George Rogers Clark to head a party into the west, presumably along the Missouri. Clark, supportive of Jefferson's intentions, declined.

While a member of Congress in 1784 Jefferson also chaired a committee to draw up plans for administering the new Northwest Territory that had been added to the United States by the Treaty of Paris of 1783. Although the original ordinance was repealed, it became the basis of the Northwest Ordinance of 1787. The latter ordinance provided for the admission of territories to statehood in stages, thus helping to lay the foundation for future growth of the nation and the disposition of western lands, including Louisiana.

In 1786, while serving as American minister at Paris, Jefferson became acquainted with the sailor and adventurer John Ledyard, to whom he proposed the enterprise of exploring the Western part of our continent, by passing thro Petersburg to Kamschatka, and procuring a passage thence in some of the Russian vessels to Nootka Sound, Whence he might make his way across the continent of America.  37 Ledyard agreed to travel to the Atlantic Coast from Paris by way of Russia, the Pacific Northwest, and the Missouri River in 1786-87, but was apprehended before reaching Russia's eastern Pacific Coast.

In 1790 Henry Knox, Secretary of War, inaugurated the first official attempt to explore the Missouri River. Knox secretly ordered Lieutenant John Armstrong to venture up the Missouri to its source and explore all of its southern branches. Poorly planned and under equipped, Armstrong's expedition never left St. Louis.

The Boston navigator and fur trader, Robert Gray, commanded the first ship to sail into the estuary of the Columbia River in May 1792. He promptly named the river after his ship, the Columbia, and established an American presence on the northwest coast of the continent, albeit without any sanction from the United States government. Equally important, he correctly fixed the longitude of the river's mouth, which set it roughly 3,000 miles west of Virginia, thus establishing, in Jefferson's mind, a more precise and permanent conception of the actual breadth of the continent.

Jefferson remained enthusiastic about mounting an expedition to explore the Northwest by way of the Missouri River. At Jefferson's urging the American Philosophical Society sponsored an expedition in 1793 by the young French naturalist, André Michaux, to find "the shortest & most convenient route of communication between the U.S. & the Pacific ocean," with the Missouri River "declared as the fundamental object."

Thomas Jefferson, letter to André Michaux, after January 23, 1793. Letterpress copy of letter, 4 pp., with transcription. Manuscript Division, Library of Congress. Thomas Jefferson Papers.

Jefferson drafted detailed instructions charging Michaux to report carefully on the topography of the region, its wildlife and flora, and its Native American inhabitants. When Michaux found himself "at the point from whence you may get by the shortest & most convenient route to some principal river of the Pacific ocean," he was "to proceed to such river, & pursue its course to the ocean." Almost as quickly as it had begun, however, Michaux's journey was aborted in Kentucky when his involvement in the intrigues of Citizen Genêt for inciting insurrection in western lands became known.

Throughout most of the 1790s Jefferson was pressed by the concerns of public service as well as private affairs at his Monticello estate. As a result he ceased planning for an expedition up the Missouri River towards the Northwest, although he never lost interest in such a venture. His vision of one day securing an "empire of liberty" stretching across both ends of the North American continent continued to fuel his desire of acquiring new lands in the effort to expand American borders towards the west.

37. Thomas Jefferson, autobiography draft fragment, entry for May 17th, 1821, 82 and 85, Thomas Jefferson Papers, Library of Congress. (Return to text)

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