Lewis and Clark Expedition
The Lewis and Clark Expedition from May 1804 to September 1806, also known as the Corps of Discovery Expedition, was the first American expedition to cross what is now the western portion of the United States. It began near St. Louis, made its way westward, and passed through the continental divide to reach the Pacific coast. The Corps of Discovery comprised a selected group of U.S. Army volunteers under the command of Captain Meriwether Lewis and his close friend, Second Lieutenant William Clark.
President Thomas Jefferson commissioned the expedition shortly after the Louisiana Purchase in 1803 to explore and to map the newly acquired territory, to find a practical route across the western half of the continent, and to establish an American presence in this territory before Britain and other European powers tried to claim it.
The campaign's secondary objectives were scientific and economic: to study the area's plants, animal life, and geography, and to establish trade with local Native American tribes. With maps, sketches, and journals in hand, the expedition returned to St. Louis to report its findings to Jefferson.
- 1 Overview
- 2 Preparations
- 3 Journey
- 4 Geography and science
- 5 Encounters with Native American nations
- 6 Accomplishments
- 7 Aftermath
- 8 Legacy and honors
- 9 Prior discoveries
- 10 See also
- 11 Notes
- 12 References
- 13 Bibliography
- 14 Further reading
- 15 External links
According to Thomas Jefferson himself, one goal was to find "the most direct and practicable water communication across this continent, for the purposes of commerce." Jefferson also placed special importance on declaring U.S. sovereignty over the land occupied by the many different tribes of Native Americans along the Missouri River, and getting an accurate sense of the resources in the recently completed Louisiana Purchase. The expedition made notable contributions to science, but scientific research was not the main goal of the mission.
During the 19th century, references to Lewis and Clark "scarcely appeared" in history books even during the United States Centennial in 1876 and the expedition was largely forgotten. Lewis and Clark began to gain new attention around the start of the 20th century. Both the 1904 Louisiana Purchase Exposition, in St. Louis, and the 1905 Lewis and Clark Centennial Exposition, in Portland, Oregon, showcased Lewis and Clark as American pioneers. However, the story remained relatively shallow, a celebration of U.S. conquest and personal adventures, until the mid-century, since which time it has been more thoroughly researched and retold in many forms to a growing audience.
In 2004, a complete and reliable set of the expedition's journals was compiled by Gary E. Moulton. In the 2000s, the bicentennial of the expedition further elevated popular interest in Lewis and Clark. As of 1984, no U.S. exploration party was more famous, and no American expedition leaders are more instantly recognizable by name.
For years, Jefferson had heard of and read accounts of the various ventures of other explorers in parts of the western frontier and consequently had a long-held interest in further exploring this largely still unknown region of the continent. In the 1780s, while Minister to France, Jefferson met John Ledyard in Paris and discussed a proposed trip to the Pacific Northwest. Jefferson had also read Captain James Cook's A Voyage to the Pacific Ocean (London, 1784), an account of Cook's third voyage, and Le Page du Pratz's The History of Louisiana (London, 1763), all of which greatly influenced his decision to send an expedition. Like Captain Cook, Jefferson also wished to discover a practical route through the Northwest to the Pacific coast. Alexander Mackenzie had already charted a route in his quest for the Pacific, first following the later-named Mackenzie River to the Arctic Ocean in 1789. Mackenzie and his party then became the first on record to cross America north of Mexico to the Pacific, when he arrived near Bella Coola in 1793—a dozen years before Lewis and Clark. Mackenzie's accounts in Voyages from Montreal (1801) informed Jefferson (who read the book at Monticello in 1802) of Britain's intent to control the lucrative fur trade of the Columbia River, and convinced him of the importance of securing the territory as soon as possible.
Two years into his presidency, Jefferson asked Congress to fund an expedition through the Louisiana territory to the Pacific Ocean. He did not attempt to hide the Lewis and Clark expedition itself from Spanish, French, and British officials, but rather claimed different reasons for the venture. He used a secret message to ask for funding due to poor relations with the opposition party in Congress.
In 1803, Jefferson commissioned the Corps of Discovery, and named U.S. Army Captain Meriwether Lewis its leader, who in turn selected William Clark as second in command. Lewis demonstrated remarkable skills and potential as a frontiersman. As the expedition was gaining approval and funding, Jefferson made efforts to prepare him for the long journey ahead. Jefferson chose Lewis to lead the expedition rather than a "qualified scientist" because, "It was impossible to find a character who to a complete science in botany, natural history, mineralogy & astronomy, joined the firmness of constitution & character, prudence, habits adapted to the woods & a familiarity with the Indian manners and character, requisite for this undertaking. All the latter qualifications Capt. Lewis has."
In 1803, Jefferson sent Lewis to Philadelphia to study medicinal cures under Benjamin Rush, a physician and humanitarian. Jefferson also arranged for Lewis to be further educated by Andrew Ellicott, an astronomer who instructed him in the use of the sextant and other navigational instruments. Lewis, however, was not ignorant of science and had demonstrated to Jefferson a marked capacity to learn, especially with Jefferson as his teacher. At Monticello, Jefferson possessed the largest library in the world on the subject of the geography of the North American continent, and Lewis had full access to that library. Lewis spent time consulting maps and books and conferring with Jefferson at Jefferson's library in Monticello.
Lewis and Clark met near Louisville, Kentucky, in October 1803 at the Falls of the Ohio and before departing later in the month, the core "Nine Young Men" were enlisted into the Corps of Discovery. Their goals were to explore the vast territory acquired by the Louisiana Purchase and to establish trade and U.S. sovereignty over the native peoples along the Missouri River. Jefferson also wanted to establish a U.S. claim of "Discovery" to the Pacific Northwest and Oregon territory by documenting an American presence there before Europeans could claim the land. According to some historians, Jefferson understood he would have a better claim of ownership to the Pacific Northwest if the team gathered scientific data on animals and plants. However, his main objectives were centered around finding an all-water route to the Pacific coast and commerce. Before their departure, Jefferson's instructions to them stated:
The object of your mission is to explore the Missouri River, & such principle stream of it, as, by its course and communication with the waters of the Pacific ocean, whether the Columbia, Oregon, Colorado or any other river may offer the most direct & practicable water communication across this continent for the purpose of commerce.
The U.S. mint prepared special silver medals with a portrait of Jefferson and inscribed with a message of friendship and peace, called Indian Peace Medals. The soldiers were to distribute them to the nations they met. These symbolized U.S. sovereignty over the indigenous inhabitants. The expedition also prepared advanced weapons to display their military firepower. Among these was an Austrian-made .46 caliber Girandoni air rifle, a repeating rifle with a 20-round tubular magazine that was powerful enough to kill a deer. The expedition was prepared with sufficient black powder and lead for their flintlock firearms, knives, blacksmithing supplies, and cartography equipment. They also carried flags, gift bundles, medicine, and other items they would need for their journey. Much time went into ensuring a sufficient supply of these items.
The route of Lewis and Clark's expedition took them up the Missouri River to its headwaters, then on to the Pacific Ocean via the Columbia River, and may have been influenced by the purported transcontinental journey of Moncacht-Apé by the same route about a century before. Jefferson had a copy of Le Page's book detailing Moncacht-Apé's itinerary in his library, and Lewis carried a copy with him during the expedition. Le Page's description of Moncacht-Apé's route across the continent, which neglects to mention the need to cross the Rocky Mountains, may be the source of Lewis and Clark's mistaken belief that they could easily carry boats from the Missouri's headwaters to the westward-flowing Columbia.
The historian John L. Loos of Louisiana State University wrote William Clark's Part in the Preparation of the Lewis and Clark Expedition, a 511-page manuscript published in 1954 by the Missouri Historical Society.
Thirty-three people, including 29 participants in training at the 1803–1804 Camp Dubois (Camp Wood) winter staging area, then in the Indiana Territory, were near present-day Wood River, Illinois, on the east bank of the Mississippi. In March 1804, the Spanish in New Mexico learned from U.S. General James Wilkinson, later discovered to be a paid agent of the Spanish crown,[note 1] that the Americans were encroaching on territory claimed by Spain.
On August 1, they sent four armed expeditions of 52 soldiers, mercenaries, and Indians from Santa Fe northward under Pedro Vial and José Jarvet, to intercept Lewis and Clark and imprison the entire expedition. When they reached the Pawnee settlement on the Platte River in central Nebraska, they learned that the expedition had been there many days before, but because the expedition at that point was covering 70 to 80 miles (110 to 130 km) a day, Vial's attempt to intercept them was unsuccessful.
The Corps of Discovery departed from Camp Dubois at 4 pm on May 14, 1804, and met up with Lewis in St. Charles, Missouri, a short time later, marking the beginning of the voyage to the Pacific coast. The Corps followed the Missouri River westward. Soon, they passed La Charrette, the last Euro-American settlement on the Missouri River.
The expedition followed the Missouri through what is now Kansas City, Missouri, and Omaha, Nebraska. On August 20, 1804, Sergeant Charles Floyd died, apparently from acute appendicitis. He had been among the first to sign up with the Corps of Discovery and was the only member to die during the expedition. He was buried at a bluff by the river, now named after him, in what is now Sioux City, Iowa. His burial site was marked with a cedar post on which was inscribed his name and day of death. 1 mile (2 km) up the river, the expedition camped at a small river which they named Floyd's River. During the final week of August, Lewis and Clark reached the edge of the Great Plains, a place abounding with elk, deer, bison, and beavers.
The Lewis and Clark Expedition established relations with two dozen Indian nations, without whose help the expedition would have risked starvation during the harsh winters and/or become hopelessly lost in the vast ranges of the Rocky Mountains.
The Americans and the Lakota nation (whom the Americans called Sioux or "Teton-wan Sioux") had problems when they met, and there was a concern the two sides might fight. According to Harry W. Fritz, "All earlier Missouri River travelers had warned of this powerful and aggressive tribe, determined to block free trade on the river. ... The Sioux were also expecting a retaliatory raid from the Omaha Indians, to the south. A recent Sioux raid had killed 75 Omaha men, burned 40 lodges, and taken four dozen prisoners."
One of their horses disappeared, and they believed the Sioux were responsible. Afterward, the two sides met and there was a disagreement, and the Sioux asked the men to stay or to give more gifts instead before being allowed to pass through their territory. They came close to fighting several times, and both sides finally backed down and the expedition continued on to Arikara territory. Clark wrote they were "warlike" and were the "vilest miscreants of the savage race".
In the winter of 1804–05, the party built Fort Mandan, near present-day Washburn, North Dakota. Just before departing on April 7, 1805, the expedition sent the keelboat back to St. Louis with a sample of specimens, some never seen before east of the Mississippi. One chief asked Lewis and Clark to provide a boat for passage through their national territory. As tensions increased, Lewis and Clark prepared to fight, but the two sides fell back in the end. The Americans quickly continued westward (upriver), and camped for the winter in the Mandan nation's territory.
After the expedition had set up camp, nearby Indians came to visit in fair numbers, some staying all night. For several days, Lewis and Clark met in council with Mandan chiefs. Here they met a French-Canadian fur trapper named Toussaint Charbonneau, and his young Shoshone wife Sacagawea. Charbonneau at this time began to serve as the expedition's translator. Peace was established between the expedition and the Mandan chiefs with the sharing of a Mandan ceremonial pipe. By April 25, Captain Lewis wrote his progress report of the expedition's activities and observations of the Indian nations they have encountered to date: A Statistical view of the Indian nations inhabiting the Territory of Louisiana, which outlined the names of various tribes, their locations, trading practices, and water routes used, among other things. President Jefferson would later present this report to Congress.
They followed the Missouri to its headwaters, and over the Continental Divide at Lemhi Pass. In canoes, they descended the mountains by the Clearwater River, the Snake River, and the Columbia River, past Celilo Falls, and past what is now Portland, Oregon, at the meeting of the Willamette and Columbia Rivers. Lewis and Clark used William Robert Broughton's 1792 notes and maps to orient themselves once they reached the lower Columbia River. The sighting of Mount Hood and other stratovolcanos confirmed that the expedition had almost reached the Pacific Ocean.
The expedition sighted the Pacific Ocean for the first time on November 7, 1805, arriving two weeks later. The expedition faced its second bitter winter camped on the north side of the Columbia River, in a storm-wracked area. Lack of food was a major factor. The elk, the party's main source of food, had retreated from their usual haunts into the mountains, and the party was now too poor to purchase enough food from neighboring tribes. On November 24, 1805, the party voted to move their camp to the south side of the Columbia River near modern Astoria, Oregon. Sacagawea, and Clark's slave York, were both allowed to participate in the vote, so this may have been the first time in American history where a woman and a slave were allowed to vote.
On the south side of the Columbia River, 2 miles (3 km) upstream on the west side of the Netul River (now Lewis and Clark River), they constructed Fort Clatsop. They did this not just for shelter and protection, but also to officially establish the American presence there, with the American flag flying over the fort. During the winter at Fort Clatsop, Lewis committed himself to writing. He filled many pages of his journals with valuable knowledge, mostly about botany, because of the abundant growth and forests that covered that part of the continent. The health of the men also became a problem, with many suffering from colds and influenza.
Lewis was determined to remain at the fort until April 1, but was still anxious to move out at the earliest opportunity. By March 22, the stormy weather had subsided and the following morning, on March 23, 1806, the journey home began. The Corps began their journey homeward using canoes to ascend the Columbia River, and later by trekking over land.
They made their way to Camp Chopunnish[note 2] in Idaho, along the north bank of the Clearwater River, where the members of the expedition collected 65 horses in preparation to cross the Bitterroot Mountains, lying between modern-day Idaho and western Montana. However, the range was still covered in snow, which prevented the expedition from making the crossing. On April 11, while the Corps was waiting for the snow to diminish, Lewis' dog, Seaman, was stolen by Indians, but was retrieved shortly. Worried that other such acts might follow, Lewis warned the chief that any other wrongdoing or mischievous acts would result in instant death.
On July 3, before crossing the Continental Divide, the Corps split into two teams so Lewis could explore the Marias River. Lewis' group of four met some men from the Blackfeet nation. During the night, the Blackfeet tried to steal their weapons. In the struggle, the soldiers killed two Blackfeet men. Lewis, George Drouillard, and the Field brothers fled over 100 miles (160 kilometres) in a day before they camped again.
Meanwhile, Clark had entered the Crow tribe's territory. In the night, half of Clark's horses disappeared, but not a single Crow had been seen. Lewis and Clark stayed separated until they reached the Yellowstone and Missouri Rivers on August 11. As the groups reunited, one of Clark's hunters, Pierre Cruzatte, mistook Lewis for an elk and fired, injuring Lewis in the thigh. Once together, the Corps was able to return home quickly via the Missouri River. They reached St. Louis on September 23, 1806.
Geography and science
The Lewis and Clark Expedition gained an understanding of the geography of the Northwest and produced the first accurate maps of the area. During the journey, Lewis and Clark drew about 140 maps. Stephen Ambrose says the expedition "filled in the main outlines" of the area.
The expedition documented natural resources and plants that had been previously unknown to Euro-Americans, though not to the indigenous peoples. Lewis and Clark were the first Americans to cross the Continental Divide, and the first Americans to see Yellowstone, enter into Montana, and produce an official description of these different regions. Their visit to the Pacific Northwest, maps, and proclamations of sovereignty with medals and flags were legal steps needed to claim title to each indigenous nation's lands under the Doctrine of Discovery.
The expedition was sponsored by the American Philosophical Society (APS). Lewis and Clark received some instruction in astronomy, botany, climatology, ethnology, geography, meteorology, mineralogy, ornithology, and zoology. During the expedition, they made contact with over 70 Native American tribes and described more than 200 new plant and animal species.
Jefferson had the expedition declare "sovereignty" and demonstrate their military strength to ensure native tribes would be subordinate to the U.S., as European colonizers did elsewhere. After the expedition, the maps that were produced allowed the further discovery and settlement of this vast territory in the years that followed.
In 1807, Patrick Gass, a private in the U.S. Army, published an account of the journey. He was promoted to sergeant during the course of the expedition. Paul Allen edited a two-volume history of the Lewis and Clark expedition that was published in 1814, in Philadelphia, but without mention of the actual author, banker Nicholas Biddle. [note 3] Even then, the complete report was not made public until more recently. The earliest authorized edition of the Lewis and Clark journals resides in the Maureen and Mike Mansfield Library at the University of Montana.
Encounters with Native American nations
One of the primary objectives of the expedition as directed by President Jefferson was to observe and record the whereabouts, lives, activities, and cultures of the various American Indian tribes that inhabited the newly acquired territory and the northwest in general. The expedition encountered many different tribes along the way, many of whom offered their assistance, providing the expedition with their knowledge of the wilderness and with the acquisition of food. Along with the standard provisions of weapons, powder, tools, and cooking utensils, the expedition also had blank leather-bound journals and ink for the purpose of recording such encounters, as well as for scientific and geological information. They were also provided with various gifts of medals, ribbons, needles, mirrors and other artifacts which were intended to ease any tensions when negotiating their passage with the various Indian chiefs they would encounter along their way.
As many of the tribes had had previous friendly experiences with British and French fur traders in various isolated encounters along the Missouri and Columbia Rivers, the expedition subsequently did not encounter any hostilities with the exception of the Teton-Sioux tribe under Black Buffalo and the Partisan tribe on September 25, 1804. Both of these tribes were rivals and hoped to use the expedition to their own advantage and who both demanded tribute from the expedition for their passage over the river at that particular juncture.
Captain Lewis made his first mistake by offering the Sioux chief gifts first, which insulted and angered the Partisan chief. Communication was difficult since the expedition's only Sioux interpreter, Pierre Dorion, had stayed behind with the other party and was also involved with diplomatic affairs with another tribe. Consequently, both chiefs were offered a few gifts, but neither was satisfied. At that point, some of the warriors from the Partisan tribe then took hold of their boat and one of the oars. Lewis took a firm stand, ordering a display of force, presenting arms; Captain Clark, by gesture of brandishing his sword, threatened violent reprisal. Just before the situation erupted into a violent confrontation, Black Buffalo ordered his warriors to back off.
After the ensuing diplomacy and with the aid of better gifts and now a bottle of whiskey, of which some was consumed, the captains were able to negotiate their passage through without further incident. During the next two days, the expedition made camp not far from Black Buffalo's tribe. When they attempted to leave, other similar incidents occurred, but they were averted with still more gifts, this time, of tobacco.
As the expedition encountered the various American Indian tribes during the course of their journey they observed and recorded information regarding their lifestyles, customs and the social codes they lived by, as directed by President Jefferson. By western standards the Indian way of life seemed harsh and unforgiving as witnessed by members of the expedition. After many encounters and camping in close proximity to the Indian nations for extended periods of time during the winter months they soon learned first hand of their customs and social orders.
One of the primary customs that distinguished Indian cultures from those of the West was that it was customary for the men to take on two or more wives if they were able to provide for them and often took on a wife or wives who were members of the immediate family circle. e.g. men in the Minnetaree [note 4] and Mandan tribes would often take on a sister for a wife. Chastity among women was not held in high regard. Infant daughters were often sold by the father to men who were grown, usually for horses or mules.
They learned that women in Sioux nations were often bartered away for horses or other supplies, yet this was not practiced among the Shoshone nation who held their women in higher regard. They witnessed that many of the Indian nations were constantly at war with other tribes, especially the Sioux, who, while remaining generally friendly to the white fur traders, had proudly boasted and justified the almost complete destruction of the once great Cahokia nation, along with the Missouris, Illinois, Kaskaskia, and Piorias tribes that lived about the countryside adjacent to the upper Mississippi and Missouri rivers.
Sacagawea, sometimes called Sakajawea or Sakagawea (c. 1788 – December 20, 1812), was a Shoshone Indian woman who arrived with her husband Toussaint Charbonneau on the expedition to the Pacific Ocean.
On February 11, 1805, a few weeks after her first contact with the expedition, Sacagawea went into labor which was slow and painful, so the Frenchman Charbonneau suggested she be given a potion of rattlesnake's rattle to aid in her delivery. Lewis happened to have some snake's rattle with him. A short time after administering the potion, she delivered a healthy boy who was given the name Jean Baptiste Charbonneau.
When the expedition reached Marias River, on June 16, 1805, Sacagawea became dangerously ill. She was able to find some relief by drinking mineral water from the sulphur spring that fed into the river.
Though she has been discussed in literature frequently, much of the information is exaggeration or fiction. Scholars say she did notice some geographical features, but "Sacagawea...was not the guide for the Expedition, she was important to them as an interpreter and in other ways." The sight of a woman and her infant son would have been reassuring to some indigenous nations, and she played an important role in diplomatic relations by talking to chiefs, easing tensions, and giving the impression of a peaceful mission.
In his writings, Meriwether Lewis presented a somewhat negative view of her, though Clark had a higher regard for her, and provided some support for her children in subsequent years. In the journals, they used the terms "squar" and "savages" to refer to Sacagawea and other indigenous peoples.
The Corps met their objective of reaching the Pacific, mapping and establishing their presence for a legal claim to the land. They established diplomatic relations and trade with at least two dozen indigenous nations. They did not find a continuous waterway to the Pacific Ocean but located an Indian trail that led from the upper end of the Missouri River to the Columbia River which ran to the Pacific Ocean. They gained information about the natural habitat, flora and fauna, bringing back various plant, seed and mineral specimens. They mapped the topography of the land, designating the location of mountain ranges, rivers and the many Indian tribes during the course of their journey. They also learned and recorded much about the language and customs of the American Indian tribes they encountered, and brought back many of their artifacts, including bows, clothing and ceremonial robes.
Two months passed after the expedition's end before Jefferson made his first public statement to Congress and others, giving a one-sentence summary about the success of the expedition before getting into the justification for the expenses involved. In the course of their journey, they acquired a knowledge of numerous tribes of Indians hitherto unknown; they informed themselves of the trade which may be carried on with them, the best channels and positions for it, and they are enabled to give with accuracy the geography of the line they pursued. Back east, the botanical and zoological discoveries drew the intense interest of the American Philosophical Society who requested specimens, various artifacts traded with the Indians, and reports on plants and wildlife along with various seeds obtained. Jefferson used seeds from "Missouri hominy corn" along with a number of other unidentified seeds to plant at Monticello which he cultivated and studied. He later reported on the "Indian corn" he had grown as being an "excellent" food source. The expedition helped establish the U.S. presence in the newly acquired territory and beyond and opened the door to further exploration, trade and scientific discoveries.
Lewis and Clark returned from their expedition, bringing with them the Mandan Indian Chief Shehaka from the Upper Missouri to visit the "Great Father" at Washington City. When Louis was appointed Governor of Missouri Territory, he sent Chief Shehaka up the Missouri with an escort of about 40 United States troops under the command of Captain Prior. On their arrival to the country of Rickarees, a warlike Indian tribe attacked the Mandans and killed eight or ten soldiers while the rest retreated with Shehaka to St. Louis. With the formation of the Missouri Fur Company, an expedition was proposed to head up the Missouri and into the Rocky Mountains during Spring of 1809. Governor Lewis contracted with the company to convey the Mandan Chief back to his tribe for the sum of $10,000. General Thomas James wrote a journal of how he enlisted in this expedition during his youth. The money was raised for trading with the Indians and trapping Beaver along the headwaters of the Missouri and Columbia rivers. The total party consisted of 350 men.
Legacy and honors
Since the expedition, Lewis and Clark have been commemorated and honored over the years on various coins, currency, and commemorative postage stamps, as well as in a number of other capacities.
Lewis & Clark were honored (along with the American bison) on the Series of 1901 $10 Legal Tender
Lewis and Clark Interpretive Center in Cape Disappointment State Park
In 1682, René-Robert Cavelier, Sieur de La Salle went down the Mississippi from the Great Lakes to the Gulf. The French then established a chain of posts along the Mississippi from New Orleans to the Great Lakes. There followed a number of French explorers including Pedro Vial and Pierre Antoine and Paul Mallet, among others. Vial may have preceded Lewis and Clark to Montana. In 1787, he gave a map of the upper Missouri River and locations of "territories transited by Pedro Vial" to Spanish authorities.
Early in 1792, the American explorer Robert Gray, sailing in the Columbia Rediviva, discovered the yet to be named Columbia River, named it after his ship and claimed it for the United States. Later in 1792, the Vancouver Expedition had learned of Gray's discovery and used his maps. Vancouver's expedition explored over 100 miles (160 km) up the Columbia, into the Columbia River Gorge. Lewis and Clark used the maps produced by these expeditions when they descended the lower Columbia to the Pacific coast.
|Wikimedia Commons has media related to Lewis and Clark National Historic Trail.|
|Wikimedia Commons has media related to Lewis and Clark Trail.|
|Wikimedia Commons has media related to Lewis and Clark Expedition.|
- The Red River Expedition (1806) and the Pike Expedition were also commissioned by Jefferson
- Gateway Arch National Park
- The Far Horizons, a movie of the expedition
- York (explorer) – the slave on the expedition
- Lewis and Clark Pass (Montana) – the only non-motorized pass on the expedition's route
- It was not discovered that Wilkinson was a spy until after his death in 1825
- 'Chopunnish' was the Captain's term for the Nez Perce Pass
- An anomaly of some proportion is the fact that the 1814 account, now commonly referred to as the Biddle edition, carried no mention of Biddle anywhere. ... The only logical explanation of this incredible omission is that Biddle wanted it that way, insisted on complete anonymity.
- aka the Hidatsa
- Woodger, Toropov, 2009 p.150
- Ambrose, 1996, Chap. VI
- Miller, 2006 p.108
- Fenelon & Wilson, 2006 pp.90–91
- Lavender, 2001 pp.32, 90
- Ronda, 1984 pp.82, 192
- Fritz, 2004 p.113
- Ronda, 1984 p.9
- Ronda, 1984 pp.327–328
- Fresonke & Spence, 2004 pp.159–162
- Moulton, 2004
- Ambrose, 1996 p.480
- Saindon, 2003 pp.vi, 1040
- Ambrose, 1996 p.69
- Gray, 2004 p.358
- DeVoto, 1997 p.xxix
- Schwantes, 1996 pp.54–55
- Rodriguez, 2002 p.xxiv
- Furtwangler, 1993 p.19
- Ambrose, 1996 p.83
- Bergon, 2003, p.xiv
- Woodger & Toropov, 2009 p.270
- "Lewis and Clark Expedition".
- Gass & MacGregor, 1807 p.7
- Ambrose, 1996 pp.79, 89
- Ambrose, 1996 p.13
- Homser, James Kendall, 1903 p.1
- Kleber, 2001 pp.509–510
- Fritz, 2004 pp.1–5
- Ronda, 1984 p.32
- Miller, 2006 pp.99–100, 111
- Bennett, 2002 p.4
- Ambrose, 1996 p.94
- Saindon, 2003 pp.551–552
- Miller, 2006 p.106
- Woodger, Toropov, 2009 pp.104, 265, 271
- Lavender, 2001 pp.30–31
- John L. Loos, William Clark's Part in the Preparation of the Lewis and Clark Expedition. Missouri Historical Society. Retrieved October 3, 2011.
- Uldrich, 2004 p.82
- Ambrose, 1996 p.402
- Peters 1996, pp. 16.
- Allen, Lewis & Clark, Vol. 1, 1916 pp.26–27
- Woodger & Toropov, 2009 p.142
- Coues, Lewis, Clark, Jefferson 1893, Vol. 1 p.79
- Fritz, 2004 p.13
- Fritz, 2004 p.14
- Fritz, 2004 pp.14–15
- Ambrose, 1996 p.170
- Ronda, 1984 pp.27, 40
- Lavender, 2001 p.181
- Peters 1996, pp. 20-22.
- Clark & Edmonds, 1983 p.12
- Allen, Lewis & Clark, Vol.1, 1916 pp.81–82
- Elin Woodger; Brandon Toropov (January 1, 2009). Encyclopedia of the Lewis and Clark Expedition. Infobase Publishing. pp. 244–245. ISBN 978-1-4381-1023-3. Retrieved August 28, 2013.
- History & Culture - Lewis and Clark National Historical Park (U.S. National Park Service)
- "Lewis and Clark, Journey Leg 13, 'Ocian in View!', October 08-December 07, 1805". National Geographic Society. 1996. Archived from the original on September 27, 2016. Retrieved October 22, 2016.
- Ambrose, 1996 p.326
- Clark & Edmonds, 1983 pp.51–52
- Harris, Buckley, 2012, p. 109
- Ambrose, 1996 p.330
- Ambrose, 1996 p.334
- Coues, Lewis, Clark, Jefferson 1893 pp.902–904
- Peters 1996, pp. 30.
- Ambrose, 1996 p.483
- Fritz, 2004 p.60
- Ambrose, 1996 p.409
- Woodger & Toropov, 2009 p.99
- DeVoto, 1997 p.552
- Woodger, Toropov, 2012 p.29
- Fritz, 2004 p.59
- Uldrich, 2004 p.37
- Fresonke & Spence, 2004 p.70
- Fritz, 2004 p.88
- Gass & MacGregor, 1807 pp.iv, 3
- Ambrose, 1996 pp.479–480
- Lewis and Clark Journals Archived January 30, 2009, at the Wayback Machine.
- Josephy, 2006 p.vi
- Allen, Lewis & Clark, Vol.1, 1916 p.52
- Ambrose, 1996 p.169
- Woodger & Toropov, 2009 pp.8, 337–338
- Coues, Lewis, Clark, Jefferson 1893, Vol. 2 pp.557–558
- Lewis, Clark Floyd, Whitehouse, 1905 p.93
- Coues, Lewis, Clark, Jefferson 1893, Vol.1 p.229
- Clark & Edmonds, 1983 p.15
- Coues, Lewis, Clark, Jefferson 1893, Vol.1 p.377
- Clark & Edmonds, 1983 p.16
- Fritz, 2004 p.19
- Clark & Edmonds, 1983 pp.16, 27
- Ronda, 1984 pp.258–259
- Fritz, 2004 pp.33–35
- Ambrose, 1996 pp.352, 407
- Ambrose, 1996 p.204
- Ambrose, 1996, p. 418
- Ambrose, 1996, p. 144
- Gen. Thomas James. Three Years Among the Indians and Mexicans. pp. 3–4. ISBN 978-1985208711.
- Loomis & Nasatir 1967 pp.382–386, map: p.290
- Ambrose, 1996 p.70, 91
- Woodger, Toropov, 2009 pp.191, 351
- Encyclopedia Britannica: Sir Alexander Mackenzie.
- Allen, Paul; Clark, William; Lewis, Meriwether (1916). Meriwether Lewis and William Clarke, Volume 1. Elliott-Madison Company. p. 366.
- ——; Clark, William; Lewis, Meriwether (1916). Meriwether Lewis and William Clarke, Volume 2. Elliott-Madison Company. p. 381.
- Ambrose, Stephen E. (1996). Undaunted Courage: Meriwether Lewis, Thomas Jefferson, and the Opening of the American West. Simon and Schuster, New York. p. 511. ISBN 9780684811079.
- Bennett, George D. (2002). The United States Army: Issues, Background and Bibliography. Nova Publishers. p. 229. ISBN 9781590333006.
- Bergon, Frank (1989). The Journals of Lewis and Clark. Penguin Classics, New York. ISBN 0142437360.
- Clark, Ella E.; Edmonds, Margot (1983). Sacagawea of the Lewis and Clark Expedition. University of California Press. p. 184. ISBN 9780520050600.
- Cutright, Paul Russell (2000). Contributions of Philadelphia to Lewis and Clark History. Lewis and Clark Trail Heritage Foundation. p. 47.
- DeVoto, Bernard Augustine (1997) . The Journals of Lewis and Clark. Houghton Mifflin Company. p. 504. ISBN 0-395-08380-X.
- —— (1998). The Course of Empire. Houghton Mifflin Harcourt. p. 647. ISBN 9780395924983.
- Fenelon, James; Defender-Wilson, Mary Louise (1985). Voyage of Domination, "Purchase" as Conquest, Sakakawea for Savagery: Distorted Icons from Misrepresentations of the Lewis and Clark Expedition. University of Minnesota Press. pp. Wicazo Sa Review, 85–104. JSTOR 1409488.
- Fresonke, Kris; Spence, Mark (2004). Lewis and Clark. University of California Press. p. 290. ISBN 9780520228399.
- Fritz, Harry W. (2004). The Lewis and Clark Expedition. Greenwood Publishing Group. p. 143. ISBN 978-0-313-31661-6.
- Furtwangler, Albert (1993). Acts of discovery: visions of America in the Lewis and Clark journals. University of Illinois Press. ISBN 978-0-252-06306-0.
- Gass, Patrick; MacGregor, Carol Lynn (1807). The Journals of Patrick Gass: Member of the Lewis and Clark Expedition. Mountain Press Publishing. p. 447. ISBN 9780878423514.
- Gray, Edward (2004). "Visions of Another Empire: John Ledyard, an American Traveler across the Russian Empire, 1787–1788". Journal of the Early Republic. University of Pennsylvania Press. 24 (3). JSTOR 4141438.
- Harris, Matthew L.; Buckley, Jay H. (2012). Zebulon Pike, Thomas Jefferson, and the Opening of the American West. University of Oklahoma Press, 256 pages. ISBN 9780806188317.
- Josephy, Alvin M., Jr.; Marc, Jaffe, eds. (2006). Lewis and Clark Through Indian Eyes. Random House Digital, Inc. p. 196. ISBN 9781400042678.
- Kleber, John (2001). The Encyclopedia of Louisville. University Press of Kentucky. p. 509. ISBN 978-0-8131-2100-0.
- Lavender, David Sievert (2001). The Way to the Western Sea: Lewis and Clark Across the Continent. University of Nebraska Press. p. 444. ISBN 9780803280038.
- Loomis, Noel M; Nasatir, Abraham P (1967). Pedro Vial and the Roads to Santa Fe. University of Oklahoma Press. ISBN 9780806111100.
- Miller, Robert J. Miller (2006). Native America, Discovered And Conquered: Thomas Jefferson, Lewis & Clark, And Manifest Destiny. Greenwood Publishing Group. p. 240. ISBN 9780275990114.
- Peters, Arthur K. (1996). Seven trail west. Abbeville Press. ISBN 1-55859-782-4.
- Saindon, Robert A. (2003). Explorations Into the World of Lewis and Clark, Volume 3. Digital Scanning Inc. p. 528. ISBN 9781582187655.
- Schwantes, Carlos. The Pacific Northwest: an interpretive history. University of Nebraska Press. p. 568. ISBN 978-0-8032-9228-4.
- Rodriguez, Junius (2002). The Louisiana Purchase: a historical and geographical encyclopedia. ABC-CLIO, Santa Barbara, California. p. 513. ISBN 978-1-57607-188-5.
- Ronda, James P. (1984). Lewis & Clark among the Indians. University of Nebraska Press. p. 310. ISBN 9780803289901.
- Uldrich, Jack (2004). Into the unknown: leadership lessons from Lewis & Clark's daring westward adventure. AMACOM Div American Mgmt Assn. p. 245. ISBN 0-8144-0816-8.
- Woodger, Elin; Toropov, Brandon (2009). Encyclopedia of the Lewis and Clark Expedition. Infobase Publishing. p. 438. ISBN 0-8160-4781-2.
- Lewis, Meriwether; Clark, William (2004). The Journals Of Lewis And Clark. Kessinger Publishing. p. 312. ISBN 9781419167997. E'books, Full view[full citation needed]
- Lewis, Meriwether; Clark, William; Floyd, Charles; Whitehouse, Joseph (1905). Original Journals of the Lewis and Clark Expedition, 1804-1806, V.6. Dodd, Mead & Company, New York. p. 280.
- Lewis, Meriwether; Clark, William (2003). Bergon, Frank, ed. The Journals of Lewis & Clark. Penguin. p. 560. ISBN 9780142437360.
- Lewis, Meriwether; Clark, William (1815). Travels to the source of the Missouri river and across the American continent to the Pacific ocean. Performed by order of the government of the United States, in the years 1804, 1805, and 1806. By Captains Lewis and Clarke. Published from the official report, and illustrated by a map of the route, and other maps. London: Longman, Hurst, Rees, Orme & Brown.
- "Review of Travels to the Source of the Missouri River ...". The Quarterly Review. 12: 317–368. January 1815.
- Lewis, William; Clark, Clark (1903). Hosmer, James Kendall, ed. History of the Expedition of Captain Lewis and Clark, 1804-5-6, Volume 1. A. C. McClurg & Company, Chicago. p. 500.
- Coues, Elliott; Lewis, Meriwether; Clark, William; Jefferson, Thomas (1893). History of the expedition under the command of Lewis and Clark: Volume 1. Francis P. Harper, New York. p. 1364.
- ——; Lewis, Meriwether; Clark, William; Jefferson, Thomas (1893). History of the expedition under the command of Lewis and Clark: Volume 2. Francis P. Harper, New York. p. 1364.
- ——; Lewis, Meriwether; Clark, William; Jefferson, Thomas (1893). History of the expedition under the command of Lewis and Clark: Volume 3. Francis P. Harper, New York. p. 1298.
- ——; Lewis, Meriwether; Clark, William; Jefferson, Thomas (1893). History of the expedition under the command of Lewis and Clark: Volume 4. Francis P. Harper, New York. p. 1298.
- Jackson, Donald Dean (1962). Letters of the Lewis and Clark Expedition: with related documents, 1783-1854. University of Illinois Press (Original from the University of Virginia). p. 728.
- Lewis, Meriwether; Clark, William (2004). Moulton, Gary E., ed. The Definitive Journals of Lewis & Clark. University of Nebraska Press. p. 357. ISBN 9780803280328.
- Steven E. Ambrose. Undaunted Courage, Meriwether Lewis, Thomas Jefferson, and the Opening of the American West. Simon and Schuster Paperbacks 1996.
- Bassman, John H. (2009). A Navigation Companion for the Lewis & Clark Trail. Volume 1, History, camp locations and daily summaries of expedition activities. John H. Bassman.
- Betts, Robert B. (2002). In Search of York: The Slave Who Went to the Pacific With Lewis and Clark. ISBN 0-87081-714-0.
- Clark, William; Lewis, Meriwether. The Journals of Lewis and Clark, 1804-1806.
- Burns, Ken (1997). Lewis & Clark: The Journey of the Corps of Discovery. ISBN 0-679-45450-0.
- Fenster, Julie M. (2016). Jefferson's America: The President, the Purchase, and the Explorers Who Transformed a Nation. Crown/Archetype. ISBN 978-0-3079-5654-5.
- Hayes, Derek (1999). Historical Atlas of the Pacific Northwest: Maps of Exploration and Discovery: British Columbia, Washington, Oregon, Alaska, Yukon. Sasquatch Books. p. 208. ISBN 9781570612152.
- Gen. Thomas James. Three Years Among the Indians and Mexicans. ISBN 978-1985208711.
- Gilman, Carolyn (2003). Lewis and Clark: Across the Divide. Washington, D.C.: Smithsonian Books. ISBN 9781588340993.
- Schmidt, Thomas (2002). National Geographic Guide to the Lewis & Clark Trail. ISBN 0-7922-6471-1.
- Tubbs, Stephenie Ambrose (2008). Why Sacagawea Deserves the Day Off and Other Lessons from the Lewis and Clark Trail. University of Nebraska Press.
- Wheeler, Olin Dunbar (1904). The Trail of Lewis and Clark, 1804–1904: A Story of the Great Exploration Across the Continent in 1804–6. New York: G.P. Putnam's Sons. p. 377.
- Full text of the Lewis and Clark journals online – edited by Gary E. Moulton, University of Nebraska–Lincoln
- "National Archives photos dating from the 1860s–1890s of the Native cultures the expedition encountered". Archived from the original on February 12, 2008.
- Lewis and Clark Expedition, a National Park Service Discover Our Shared Heritage Travel Itinerary
- "History of the Expedition Under the Command of Captains Lewis and Clark: To the Sources of the Missouri, thence Across the Rocky Mountains and down the River Columbia to the Pacific Ocean" published in 1814; from the World Digital Library
- Lewis & Clark Fort Mandan Foundation: Discovering Lewis & Clark