Envisaging the West: Thomas Jefferson and the Roots of Lewis and Clark

October 7, 1763 | Treaty Proclamation of 1763. In the aftermath of the French and Indian War, the British crown issued this proclamation, which severely limited colonists' access to land west of an imaginary line running down the crest of the Appalachain Mountains. With this attempt to reorganize British control in North America and maintain orderly relations with Native peoples, George III further alienated colonists who saw western expansion as an inevitable process. Many provisions in the Proclamation remained intact until 1776, although incursions by colonists into land west of the Proclamation Line were common.

July 11, 1790 | Letter Thomas Jefferson to James Monroe, July 11, 1790 Thomas Jefferson writes to James Monroe about paying the public debt and Congress' willingness to do so. Jefferson believes establishing the nation's credit is critical to showing its ability to go to war should England and Spain do so. Jefferson hopes to avoid conflict: "Our object is to feed & theirs to fight." Jefferson worries that English and Spanish designs on North America would leave the United States surrounded by potential aggressors.

August 2, 1790 | Letter Thomas Jefferson to William Carmichael, August 2, 1790 The importance of the Mississippi River to American growth and economic success is uppermost in Jefferson's mind as Spain and England seem on the brink of war.

August 28, 1790 | Report Thomas Jefferson to George Washington, August 28, 1790 Thomas Jefferson responds to George Washington's concerns, expressed in his August 27, 1790 report to Jefferson, over British expansion in the West. Jefferson is particularly concerned with the United States' position in the event of a conflict between England and Spain.

March 18, 1792 | Report Thomas Jefferson to George Washington, March 18, 1792 A detailed examination of the current and future prospect for western expansion and the legal and political ramifications of such movement.

May 26, 1801 | Letter Thomas Jefferson to James Monroe, May 26, 1801 Thomas Jefferson writes to James Monroe of business dealings and then mentions his fear that Spain would cede Louisiana and the Floridas to the French.

March 3, 1803 | Letter Thomas Jefferson to William Dunbar, March 3, 1803 After thanking William Dunbar for earlier correspondence, including Martin Duralde's report to the American Philosophical Society, Thomas Jefferson expresses hopes that American rights to the Mississippi River can be maintained without war; the President also anticipates the acquisition of Native lands on the left bank of the river to "plant on the Missisipi itself the means of it's own defence."

August 9, 1803 | Letter Thomas Jefferson to John Dickinson, August 9, 1803 Thomas Jefferson expresses his pleasure at the Louisiana Purchase, and explains the importance of the territory as a buffer against Spanish expansion.

September 21, 1803 | Letter Thomas Jefferson to William Dunbar, September 21, 1803 Thomas Jefferson questions William Dunbar about Spanish borders in the Louisiana Territory.

October 21, 1803 | Letter William Dunbar to Thomas Jefferson, October 21, 1803 William Dunbar responds to Thomas Jefferson's September 21 letter regarding the Spanish presence in Florida and the Gulf Coast and the surveys conducted by the Spanish in that region. He also praises Daniel Clark's summation of the population of the Lousiana Territory and suggests a representative from that region appear before Congress, but notes that the Spanish government is unlikely to allow such a measure to take place as long as the territory is in their hands.

October 21, 1803 | Letter William Dunbar to Thomas Jefferson, October 21, 1803 William Dunbar writes to Thomas Jefferson regarding the Spanish presence in Florida and the Gulf Coast and the surveys conducted by the Spanish in that region. He also praises George Rogers Clark's summation of the population of the Lousiana Territory and suggests a representative from that region appear before Congress, but notes that the Spanish government is unlikely to allow such a measure to take place as long as the territory is in their hands.

March 13, 1804 | Letter Thomas Jefferson to William Dunbar, March 13, 1804 Thomas Jefferson thanks William Dunbar for his letter of January 28, promising to forward his paper on the Mississippi River to the American Philosophical Society. Jefferson then writes a detailed discussion of the science of water in a river like the Mississippi. Jefferson also relates his plans for directing surveying parties to the Mississippi and Ohio Rivers, in addition to explorations of the Red and other more southern waterways. Jefferson concludes with speculations on the future of the Lousiana Territory.

April 6, 1804 | Report William Dunbar to the American Philosophical Society, via Thomas Jefferson, read April 6, 1804. The Mississippi River, its delta, and the surrounding region receive detailed attention from William Dunbar in this report forwarded to the APS by Thomas Jefferson.

May 13, 1804 | Letter William Dunbar to Thomas Jefferson, May 13, 1804 William Dunbar thanks Thomas Jefferson for his comments about Dunbar's notes on the Mississippi River. Spain's land sales in Western Florida draw the author's attention and Dunbar offers approval of continuing explorations on America's western rivers, while bemoaning Congress' reluctance to adequately fund such expeditions.