Lewis and Clark Expedition

Lewis and Clark expedition, 1803–6, U.S. expedition that explored the territory of the Louisiana Purchase and the country beyond as far as the Pacific Ocean.

Purpose

Thomas Jefferson had long considered the project of a western expedition, having encouraged John Ledyard when he proposed such an expedition in the 1780s, and as president he contemplated the matter in earnest and discussed it with his private secretary, Capt. Meriwether Lewis. When Congress approved the plan in 1803 and appropriated money for it, Jefferson named Lewis to head it, and Lewis selected William Clark as his associate in command. The purpose was to search out a land route to the Pacific, to strengthen American claims to Oregon territory, and to gather information about the indigenous inhabitants and the country of the Far West. Before the long march was begun, the Louisiana Purchase was made, increasing the need for a survey of the West.

The Expedition

The men were gathered and in the winter of 1803–4 were trained in Illinois across the Mississippi from St. Louis, the starting point. In May, 1804, they set out up the Missouri, and the next winter was spent at the Mandan villages (near present Bismarck, N.Dak.). In 1805 the hardest part of the journey was made. After reaching the Three Forks of the Missouri River (and naming the three branches after Jefferson, Madison, and Gallatin in loyalty to the administration), they followed the Jefferson as far as they could. Then their Shoshone guide, the remarkable woman Sacajawea, helped to obtain horses for them to continue across the high Rockies. They crossed the Continental Divide at Lemhi Pass and went over the Bitterroot Mts. through Lolo Pass. They had reached the land of westward-flowing rivers, and for part of their way they followed the Clearwater River down to the Snake River (long called the Lewis). The Snake took them to the Columbia River and they spent a miserable, rainy winter season in Fort Clatsop, a crude post they built on the Pacific coast.

In the spring they started back across the continent. In July, 1806, the party split for a time in order to explore as much territory as possible. Lewis went with a group down the Marias River, while Clark and most of the men descended the Yellowstone River; they were reunited on the Missouri at the mouth of the Yellowstone on Aug. 12, 1806. The party arrived in St. Louis on Sept. 23, 1806, and were greeted with much acclaim. The route of the expedition is commemorated by a series of sites along the

Lewis and Clark National Historic Trail (see National Parks and Monuments

acres (hectares)

Description
Acadia NP SE Maine 1919 48,419 (19,603) Mountain and coast scenery.
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The importance of the well-planned, well-executed expedition (only one person had been lost) was enormous. Although it was not the first transcontinental crossing in the north (Alexander Mackenzie had preceded them in a remarkable voyage), it opened vast new territories to the United States. Its influence on the history of the West is incalculable. Its results matched the efficiency and capability of its leaders.

Bibliography

Since the journey was under official auspices, many records were kept. The first report of it to be published appeared in a message of President Jefferson in 1806. In 1807 the journal of Patrick Gass appeared; it was several times reissued before The History of the Expedition under the Command of Captains Lewis and Clark was published (ed. by N. Biddle and P. Allen, 2 vol., 1814; repr. 1966). This appeared in later editions by E. Coues (4 vol., 1893; repr. 1965) and J. B. McMaster (1904). R. G. Thwaites edited a full issue of Original Journals of the Lewis and Clark Expedition (8 vol., 1904–5; repr. 2001; abridged ed. by B. DeVoto, 1953, repr. 1963) and G. E. Moulton edited a definitive edition of the journals of Lewis, Clark, and members of the Corps of Discovery published as The Journals of the Lewis and Clark Expedition (13 vol., 1983–2002, abridged ed. 2003).

There have been many studies and monographs on the expedition. See study by J. Bakeless (1947, repr. 1962). See also Letters of the Lewis and Clark Expedition (ed. by D. D. Jackson, 1962); R. H. Dillon, Meriwether Lewis: A Biography (1968); P. R. Cutright, Lewis and Clark, Pioneering Naturalists (1969); D. S. Lavender, The Way to the Western Sea (1988).

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Lewis and Clark Expedition

(1804–06) First overland expedition to the U.S. Pacific coast and back, led by Meriwether Lewis and William Clark. Initiated by Pres. Thomas Jefferson, the expedition set out to find an overland route to the Pacific, documenting its exploration through the new Louisiana Purchase. About 40 men, skilled in various trades, left St. Louis in 1804. They traveled up the Missouri River into present-day North Dakota, where they built Fort Mandan (later Bismarck) and wintered among the Mandan Sioux. They left the next spring, hiring Toussaint Charbonneau and his Indian wife, Sacagawea, who served as guide and interpreter. They traveled through Montana and by horse over the Continental Divide to the headwaters of the Clearwater River. They built canoes to carry them to the Snake River and then to the mouth of the Columbia River, where they built Fort Clatsop (later Astoria, Ore.) and spent the winter. On the journey back the group divided, then reunited to canoe down the Missouri to St. Louis, arriving to great acclaim in September 1806. All but one member of the expedition survived. The journals kept by Lewis and others documented Indian tribes, wildlife, and geography and did much to dispel the myth of an easy water route to the Pacific.

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Lewis and Clark Expedition

proved feasibility of overland route to the Pacific. [Am. Hist.: Benét, 583]

See : Exploration