LEWIS AND CLARK EXPEDITION

LEWIS AND CLARK EXPEDITION. In 1803, President Thomas Jefferson purchased from France the extensive Louisiana Territory, a vast tract of land comprising nearly two-thirds of the present trans-Mississippi United States. Jefferson was a leading proponent of scientific expansion, a program of planned westward growth that called for the systematic exploration and mapping of new territory prior to settlement. Believing the Louisiana Territory held nearly unlimited potential for the future growth of the United States, Jefferson appointed his personal secretary, a twenty-nine-year-old army captain named Meriwether Lewis, as commander of an expedition to explore the vast region and to locate a water route to the Pacific Ocean. Lewis in turn chose Lieutenant William Clark, a thirty-three-year-old army officer and fellow Virginian, as his cocaptain. Late in 1803, Lewis and Clark established their headquarters at St. Louis, where they spent the winter gathering supplies and training the twenty-five soldiers under their command for the arduous journey.

The expedition set out for the unknown in the spring of 1804. Most of the first summer was spent making a difficult ascent up the Missouri River to present-day North Dakota, where the expedition wintered among the villages of the Mandan Sioux. When the expedition moved out the next spring, it was joined by the French-Canadian fur trader and interpreter Toussaint Charbonneau and his Shosone Indian wife, Sacagawea, who emerged as the party's principal guide. With Sacagawea in the lead, carrying her infant son much of the way, Lewis and Clark reached the headwaters of the Missouri and then pushed westward across the Bitterroot Mountains in Montana and Idaho late in the summer of 1805. That autumn the expedition crossed the Continental Divide and descended the Clearwater and Snake Rivers. On 7 November 1805, their canoes reached the mouth of the Columbia River, and the explorers at last laid eyes upon the Pacific Ocean. They built a small wooden post, Fort Clatsop, along the Columbia River as their winter headquarters and embarked upon the return voyage the following March. After recrossing the Rocky Mountains, Lewis and Clark divided the expedition into three groups to map more territory and reunited near the convergence of the Yellowstone and Missouri Rivers. Finally, after nearly twenty-eight months of exploration and travail, the weary expedition arrived to a hero's welcome at St. Louis on 23 September 1806.

In accordance with Jefferson's detailed instructions for the expedition, Lewis and Clark brought back a multitude of scientific information, including maps, the bones and hides from animal specimens, and caged birds and prairie dogs. Of the utmost value were their voluminous journals and diaries, which provided detailed firsthand descriptions

of the plant and animal life, geography, and Native peoples encountered during the journey. Although Lewis and Clark failed to locate a convenient water passage to the Pacific Ocean, they were nonetheless handsomely rewarded for their efforts. The U.S. government awarded both men 1,600 acres of land, while each member of the expedition received 320 acres and double pay. Lewis was later appointed governor of the Louisiana Territory, while Clark held a similar post in the Missouri Territory. Their most lasting achievement, however, was their contribution to the opening, both figurative and real, of the American West.

BIBLIOGRAPHY

Ambrose, Stephen E. Undaunted Courage: Meriwether Lewis, Thomas Jefferson, and the Opening of the American West. New York: Simon and Schuster, 1996.

Duncan, Dayton. Lewis and Clark: An Illustrated History. New York: Knopf, 1997.

Moulton, Gary E., ed. The Journals of the Lewis and Clark Expedition. 13 vols. Lincoln: University of Nebraska Press, 1983–2001.

Ronda, James P., ed. Voyages of Discovery: Essays on the Lewis and Clark Expedition. Helena: Montana Historical Society Press, 1998.

Daniel P.Barr

See alsoExplorations and Expeditions: U.S. ; Louisiana Purchase ; andvol. 9:Message on the Lewis and Clark Expedition ; The Journals of the Lewis and Clark Expedition .

Lewis and Clark expedition (1804–06) The most important transcontinental journey in US history. The expedition was commissioned by President JEFFERSON to explore the vast area acquired as a result of the LOUISIANA PURCHASE. Commanded by Meriwether Lewis and William Clark, it left St Louis in 1804 and sailed up the Missouri to winter in North Dakota before crossing Montana to the foothills of the Rockies. Crossing the Continental Divide at Lemhi Pass, Idaho, the expedition then moved north and in November 1805 reached the Pacific via the Clearwater, Snake, and Columbia rivers. In 1806, after crossing the Rockies, the expedition returned.

Lewis and Clark Expedition (1804–06) US expedition to seek a route by water from the Mississippi to the Pacific Ocean. Instigated by President Thomas Jefferson, it was led by army officers Meriwether Lewis and William Clark, with the assistance of a Shoshone woman, Sacajawea. It reached the Pacific at the mouth of the Columbia River and produced valuable information about the country and peoples of the Northwest.

Lewis and Clark Expedition, see Lewis, Meriwether.