In this essay, I shall use primary sources to measure the short term significance of the Lewis and Clark Expedition (1803-1806), focussing on documents to and from Thomas Jefferson.

Jefferson emphasises the geographical nature of the trip to the Spanish Minister in December 1802 which pre-dates his ‘secret’ message to Congress, suggesting that he trusted the Spanish more (and the English and French he made the same approach to). His reasons for exploring this uncharted territory were with ‘no other view than the advancement of geography.’ By the time the Expedition started, the unexpected Louisiana Purchase meant that United States’ territory had nearly doubled and permission was no longer needed to cross foreign territory.

Jefferson had always had an interest in Science and had wanted to explore the West for a long time. His ‘rough draft of instructions’  to Meriwether Lewis were first sent in April 1803 for approval and amendment by Jefferson’s Cabinet and several leading scientists, the same men who later taught Lewis about their subjects so that he could better observe and record  what he came across on the Expedition. Again the word ‘secrecy ’is used because although there is public knowledge about exploration of the Mississippi, it ‘masks sufficiently the real destination’ which, at this point, is still on territory that belongs to others.

The final version of the Instructions, dated June 20, 1803 provide a very detailed list of Jefferson’s expectations. The principal objective is to ‘explore the Missouri river’ to see if it ‘may offer the most direct & practicable water communication across this continent for the purposes of commerce.’ A careful mapping exercise is to be undertaken. Not only are their ‘observations ..to be taken with great pains & accuracy, to be entered distinctly & intelligibly for others’ but they should make multiple copies ( in case the originals were destroyed). They will need to study the soil, animals, vegetation, minerals and climate. They must get to know the Indian tribes very well, studying relations between tribes, their customs and laws as well as trading opportunities. This knowledge will ‘enable those who may endeavour to civilize & instruct them’. They are to ‘treat them in the most friendly & conciliatory manner,’ inviting them to visit the United States. They are to come back if they are in danger for fear of losing ‘the information you will have acquired’ as much as for loss of life. Jefferson returns to commercial aspects wondering  whether ‘trade be consequently conducted through the Missouri & U.S. more beneficially than by the circumnavigation now practised’, that is, by finding a transcontinental navigable route to the Western Ocean, trade with the China markets might be made easier and more profitable. There is much more of a stress on the scientific nature of the Expedition although it is clear from Jefferson’s address to Congress and his approach to the Spanish that he is combining his scientific curiosity with his foreign and his economic policies in this Expedition. The results of the Expedition and the short term consequences can be mapped against all these documents.

 The letter was a private communication between the President, with all the authority of his office, and a trusted subordinate, therefore highly reliable as a source. It also has the status of an order from the Commander-in-Chief to a captain in the army. It is also reliable because it sets out as clearly as possible what Lewis is expected to achieve. Jefferson emphasises the crucial importance of the information gathered on the expedition by requiring copies to be made of all observations and, even as he asks for details to be kept of Native American customs, he reveals his sense of the intrinsic superiority of whites over them (“civilize and instruct”).

In Meriwether Lewis’s first letter to Jefferson sent on his return to St Louis in September 1806, he starts with the success (original spellings used): ‘in obedience to your orders we have penetrated the Continent of North America to the Pacific Ocean, and sufficiently explored the interior of the country to affirm with confidence that we have discovered the most practicable rout which dose exist across the continent’ perhaps to soften the blow that they have not found a single navigable route. As instructed, he informs the President of the depth and length of each river and the land routes, as well as the months of snow that might obstruct easy trade. He tries to stress the positive: ‘We view this passage across the Continent as affording immence advantages to the fur trade’ before acknowledging that Cape of Good Hope will still be the preferable route to foreign markets. He warns that the British have plans to ‘engroce the fur trade of the Missouri’ and that the United States needs to be vigilant. He ends the letter by telling Jefferson about the samples of plants, vocabularies and animal skins he has brought from the Expedition. He will also be bringing the Chief of the Mandan Nation with him to Washington. In other words, although he cannot provide the navigable route Jefferson so wanted, he has followed his instructions in everything else and he has found an overland route.

The list of all the animals and plants and the tribes that the Expedition encountered is extensive They identified 122 undiscovered species of animal and 178 new plants, some of which they named after themselves, for example, Philadelphus lewisii (Mock Orange) and Clarkia pucella (Ragged Robin). Lewis, in particular, detailed all his observations meticulously. He used the lessons he had had from Jefferson’s academic friends in botany, zoology, celestial navigation and medicine. These are reliable accounts of the observations he had made since he had been trained before setting out in scientific observation. 

            Lewis and Clark practised diplomacy with the American Indians as instructed. They handed out peace medals and certificates as a symbol of American sovereignty over the land and the people. In their speeches, Lewis and Clark referred to the American Indians as ‘children’ while the American Indians called Lewis and Clark ‘father’.  In a speech to visiting Indian Chiefs in early 1806 Jefferson stresses his wish for peaceable trade. The French, English and Spanish have agreed ‘to retire from all the country which you & we hold....We are now your fathers; and you shall not lose by the change’ ie the Indians should trade solely with the United States. He continues ‘My children, we are strong, we are numerous as the stars in the heavens, & we are all gun-men.’  Jefferson wants the Chiefs to spread the word ‘to tell all your people all you see’ because he wants to impress on all the tribes the power of the United States as well as their wish to form trading relationships. This is a record of a public address to the leaders of the native Americans with a clear goal to persuade the Native Americans to trade exclusively with the Americans. The rhetoric of the speech implies the natural subordination of the Native Americans (‘children’) to their caring fathers, while at the same time containing a barely hidden threat of violence (‘we are all gun-men’).

Lewis and Clark showed a genuine interest in their ways of living, forming friendly relations with most of them. The Indians’ local knowledge helped them achieve their ambition. Lewis and Clark meticulously recorded every detail of their lives providing the most complete record of Native American Indian tribes before their way of life was changed by American exploitation. It was partly because of this mutual respect that the Indians were willing to maintain relationships. However, the setting up of the factory system which would mean the Native Americans were dependent on the United States’ for trade and gave the government control over the Native Americans with Jefferson writing to Lewis that ‘Commerce is the great engine by which we are to coerce them [the Indians], not war.’ The fur factory system was an instrument to ‘civilize and instruct’ or assimilate the Native American into American civilisation. Again this is a private communication between the president and a subordinate in which the president discloses the cynical intentions of American policy. It assumes that Lewis will agree with the cynical intentions (‘coerce’) of which he will be a compliant agent. However, the fact the president wants to avoid violence is clearly important. As is his belief that trade bring peace rather than war.

In 1814 Biddle’s edition of the journals, was published. It included a copy of one of the maps that Clark had produced. Steffen, an American historian highlights Clark’s contribution to the Expedition, as ‘the maps that he brought back with him are, to the present time, considered remarkable in their accuracy and quality.’ If compared to the 1795 Arrowsmith map, it can be seen how much information is included. This information hugely increased knowledge of this region which had been very limited and eventually influenced Western expansion in the form of overland immigration, cementing America’s claim to the region.

Lewis and Clark carried out their instructions to the letter. They came back with detailed knowledge of geography, botany, zoology, cartography and ethnography which had an immediate short term significance in the increase of knowledge.  They lay claim to the lands they crossed and established their sovereignty over Indian tribes. Their Expedition laid the foundations of the Republic and had a profound impact on foreign and domestic politics and economics. Above all they showed a pioneering spirit, an ‘undaunted courage’ which would symbolise American ideals.

(1982 words)