Thomas Jefferson
Historical Figure

Thomas Jefferson

Thomas Jefferson, the third President of the United States, was the architect and primary sponsor of the Lewis and Clark Expedition. His lifelong fascination with the American West, combined with the strategic opportunity presented by the Louisiana Purchase of 1803, led him to commission the Corps of Discovery under the command of his private secretary, Meriwether Lewis. Jefferson drafted the detailed instructions for the expedition, emphasizing scientific observation, diplomatic relations with Native nations, and the search for a commercially viable route to the Pacific. He personally supervised Lewis's preparation, arranging training with leading scientists in Philadelphia. The expedition fulfilled Jefferson's vision of American expansion and scientific inquiry, though the hoped-for all-water route to the Pacific proved not to exist.

Portrait: Rembrandt Peale, 1800, White House Collection, Public Domain

0 treaties 70 total items 55 mapped locations

Related Locations

Pin color = Planning (1801–1804) Westward (1804–1805) Fort Clatsop (1805–1806) Return (1806) Post (1806–1812)
Master expedition route

Note: the longest gap between tagged appearances is about 6 months (Aug 13, 1805 → Feb 14, 1806). Thomas Jefferson may have been present in the corps during that span but is not named in the journals.

Journal Entries (55)

Clark: September 17, 1806
Sep 17, 1806 · William Clark
Clark: September 12, 1806
Sep 12, 1806 · William Clark
Clark: September 3, 1806
Sep 3, 1806 · William Clark
Clark: August 22, 1806
Aug 22, 1806 · William Clark
Clark: August 15, 1806
Aug 15, 1806 · William Clark
Clark: July 23, 1806
Jul 23, 1806 · William Clark
Clark: July 14, 1806
Jul 14, 1806 · William Clark
Clark: July 10, 1806
Jul 10, 1806 · William Clark
Clark: July 8, 1806
Jul 8, 1806 · William Clark
Clark: July 2, 1806
Jul 2, 1806 · William Clark
Clark: July 1, 1806
Jul 1, 1806 · William Clark
Lewis: July 1, 1806
Jul 1, 1806 · Meriwether Lewis
Lewis: June 25, 1806
Jun 25, 1806 · Meriwether Lewis
Clark: June 25, 1806
Jun 25, 1806 · William Clark
Clark: June 4, 1806
Jun 4, 1806 · William Clark
Clark: May 29, 1806
May 29, 1806 · William Clark
Lewis: May 10, 1806
May 10, 1806 · Meriwether Lewis
Lewis: May 11, 1806
May 11, 1806 · Meriwether Lewis
Lewis: May 5, 1806
May 5, 1806 · Meriwether Lewis
Clark: May 6, 1806
May 6, 1806 · William Clark
Lewis: May 6, 1806
May 6, 1806 · Meriwether Lewis
Clark: May 5, 1806
May 5, 1806 · William Clark
Lewis: April 29, 1806
Apr 29, 1806 · Meriwether Lewis
Clark: April 29, 1806
Apr 29, 1806 · William Clark
Clark: April 22, 1806
Apr 22, 1806 · William Clark
Lewis: April 22, 1806
Apr 22, 1806 · Meriwether Lewis
Clark: April 20, 1806
Apr 20, 1806 · William Clark
Lewis: April 6, 1806
Apr 6, 1806 · Meriwether Lewis
Clark: April 7, 1806
Apr 7, 1806 · William Clark
Clark: April 3, 1806
Apr 3, 1806 · William Clark
Clark: April 2, 1806
Apr 2, 1806 · William Clark
Clark: March 30, 1806
Mar 30, 1806 · William Clark
Clark: February 14, 1806
Feb 14, 1806 · William Clark
Lewis: February 14, 1806
Feb 14, 1806 · Meriwether Lewis
Clark: August 21, 1805
Aug 21, 1805 · William Clark
Lewis: August 18, 1805
Aug 18, 1805 · Meriwether Lewis
Lewis: August 13, 1805
Aug 13, 1805 · Meriwether Lewis
Lewis: August 14, 1805
Aug 14, 1805 · Meriwether Lewis
Lewis: August 15, 1805
Aug 15, 1805 · Meriwether Lewis
Lewis: August 10, 1805
Aug 10, 1805 · Meriwether Lewis
Clark: August 7, 1805
Aug 7, 1805 · William Clark
Lewis: August 7, 1805
Aug 7, 1805 · Meriwether Lewis
Clark: August 8, 1805
Aug 8, 1805 · William Clark
Lewis: August 9, 1805
Aug 9, 1805 · Meriwether Lewis
Lewis: August 6, 1805
Aug 6, 1805 · Meriwether Lewis
Lewis: July 30, 1805
Jul 30, 1805 · Meriwether Lewis
Lewis: July 31, 1805
Jul 31, 1805 · Meriwether Lewis
Clark: April 2, 1805
Apr 2, 1805 · William Clark
Clark: April 3, 1805
Apr 3, 1805 · William Clark
Clark: October 29, 1804
Oct 29, 1804 · William Clark
Clark: October 13, 1804
Oct 13, 1804 · William Clark
Clark: August 31, 1804
Aug 31, 1804 · William Clark
Lewis: May 20, 1804
May 20, 1804 · Meriwether Lewis
Meriwether Lewis: April 7, 1805
Apr 7, 1805 · Meriwether Lewis
Meriwether Lewis: May 26, 1805
May 26, 1805 · Meriwether Lewis

Cross-Narrator Analyses

Analyses that cite or discuss Thomas Jefferson — showing 9 of the most recent matches.

Figure: Thomas Jefferson

Thomas Jefferson: The Distant Architect of the Voyage of Discovery

An Absent PresenceThomas Jefferson never set foot on the expedition trail, yet his shadow falls across the journals from St. Louis to…

April 3, 1805

Cargo Manifests and Candid Confessions: Three Voices on the Eve of Departure

The entries of April 3, 1805, capture the Corps of Discovery on the threshold of its journey into unmapped country. The barge…

April 2, 1805

Cargo, Correspondence, and a Chief’s Departure: Three Views of Fort Mandan’s Final Days

The entries of April 2, 1805 from Fort Mandan present a study in narratorial division of labor. Three men — Sergeant Patrick…

September 4, 1805

Frozen Moccasins and White Robes: Two Sergeants Witness the Salish Encounter

The journals of Joseph Whitehouse and John Ordway for September 4, 1805, run so closely in parallel that they invite direct comparison…

September 7, 1804

The Prairie Dog Village and a Discrepancy in the Journals

The journal entries for September 7, 1804 present a striking case of narrative divergence among the expedition's enlisted chroniclers. Patrick Gass and…

August 15, 1806

The Sioux in the Road: Why No Mandan Chief Would Travel to Washington

The entries of August 15, 1806, written near the Mandan villages on the return journey, reveal a stark divergence in narrative scope.…

Figure: Karl Bodmer

Karl Bodmer: A Note on Absence from the Lewis & Clark Journals

OverviewThis biographical synthesis is unusual because it must begin with a clarification: Karl Bodmer (1809–1893), the Swiss-born painter whose watercolors and aquatints…

Narrator: Meriwether Lewis

The Captain’s Eye: Meriwether Lewis as Naturalist, Quartermaster, and Reluctant Diarist

VoiceMeriwether Lewis writes in a register that is at once military, scientific, and quietly literary. Where William Clark tends toward terse navigational…

Figure: Teton Sioux (Lakota)

The Teton Sioux (Lakota): Gatekeepers of the Upper Missouri

Introduction: A Single Entry, A Defining ConfrontationThe journal record provided here is exceptionally limited — only one entry (September 25, 1804) explicitly…

From the Heacock Memorial Archive

10 lewis-clark.org articles that mention Thomas Jefferson, preserved here for Robert Heacock’s photography. The articles were written by that site’s contributing authors.

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