The Lewis and Clark Expedition was woven into the tapestry of one of the most significant events in the history of the United States of America—the Louisiana Purchase. This timeline details the significant events with excerpts from—and hyperlinks to—the primary sources.
January 10, 1803
Monroe's extraordinary mission
Washington, DC President Jefferson writes a letter to James Monroe asking him to become Envoy Extraordinary and Minister Plenipotentiary to negotiate a solution to the Spanish closure of the port of New Orleans and their cession of Louisiana to France.
January 11, 1803
Louisiana negotiations proposed
Washington, DC Jefferson’s proposal to negotiate a solution to Spain’s cession of Louisiana to France and the closure of New Orleans commercial traffic is read to the U.S. Senate in an executive session.
January 12, 1803
Envoys Livingston and Monroe
Washington, DC President Jefferson writes the commission appointing Robert Livingston and James Monroe to negotiate a cession of land in the lower Mississippi and eastward toward Florida.
January 18, 1803
Western Expedition proposed
Washington, DC Meriwether Lewis delivers President Thomas Jefferson’s confidential message to the U.S. Congress proposing that they fund an expedition to the Western ocean.
January 24, 1803
Jefferson's coast guard solution
Washington, DC In a memo to Albert Gallatin, Thomas Jefferson proposes mooring a ship opposite New Orleans to act as a temporary customs house until a permanent solution to port’s closure can be arranged.
January 31, 1803
Spanish unease
In Washington City, the Spanish minister to the United States writes an update on the progress of President Jefferson’s proposal to send an expedition to the Pacific ocean—an act Spain opposes.
February 3, 1803
Livingston's update
President Jefferson writes the U.S. envoy in Paris telling him that ministers will be sent to negotiate a peaceful solution to the New Orleans closure—an effort resulting in the Louisiana Purchase.
February 5, 1803
Kentucky militants
James Madison summarizes Spain’s request that he do something about the militants from Kentucky who are organizing to open the port of New Orleans by force. The Louisiana Purchase would ultimately result.
February 8, 1803
Stopping unauthorized forces
President Jefferson recommends that any unauthorized groups intent on opening the port of New Orleans by force be arrested. The peaceful solution would be the Louisiana Purchase.
February 11, 1803
Jefferson's letter of credence
Washington, DC President Jefferson writes a letter of credence to Napoleon Bonaparte granting the powers of a full ambassador—without the title—to James Monroe and Robert Livingston.
February 14, 1803
The faithless Federalists
Senator James Ross raises his Mississippi Question regarding the closure of New Orleans. Ultimately, an answer will be needed before the Western expedition can begin.
February 16, 1803
The "Mississippi Question"
Washington, DC Senator James Ross of Pennsylvania continues his speech regarding the “Mississippi Question.” He recommends ending the Spanish closure of New Orleans to American navigators via military action.
February 18, 1803
Livingston's strategy
Paris, France French envoy Robert Livingston explains his strategy to convince France to cede territory in West Florida and Louisiana. Jefferson advances Lewis $15.
February 19, 1803
Stoddard's orders
Washington, DC Captain Stoddard receives orders to pick up tools at Fort Fayette and proceed to Kaskaskia, and Thomas Jefferson criticizes Senator Ross’ attempt to raise a force to take New Orleans by force.
February 25, 1803
The "two million" bill
Washington, DC Thomas Jefferson tells James Monroe that his recently authorized expedition will explore the Mississippi River.
March 2, 1803
Madison's instructions
Washington, DC James Madison writes his instructions for negotiations with France, Thomas Jefferson asks Robert Patterson to tutor Meriwether Lewis, and the Board of Agriculture’s appeal to the American citizens is published.
March 3, 1803
Jefferson's Mississippi strategy
Washington, DC President Jefferson writes to a naturalist, surveyor, and scientist living in the Mississippi Territory, William Dunbar, explaining his strategy for obtaining New Orleans and the Floridas.
March 7, 1803
Monroe travels to Paris
New York Harbor James Monroe and his family wait for the weather to allow their ship, the Richmond, to leave New York. He has been sent to assist with the Louisiana negotiations in Paris.
March 16, 1803
Jefferson's letter made public
Richmond, VA The Richmond Recorder reprints Thomas Jefferson’s letter to Kentucky governor James Gerrard, explaining the administration’s effort to solve the closure of New Orleans through diplomatic means.
March 17, 1803
No movement in New Orleans
Monticello, VA President Thomas Jefferson replies to a letter from Secretary of State James Madison saying that the Intendant of New Orleans refuses to open the port of New Orleans to American commercial traffic.
March 19, 1803
Lewis at Harpers Ferry
Harpers Ferry, WV From a letter written in April, we know that Meriwether Lewis is at the Harpers Ferry armory securing weapons, powder and lead, and overseeing construction of the iron-framed boat. President Jefferson discusses Louisiana negotiation strategy.
March 22, 1803
Federalist folly
Monticello, VA Writing from his home, Monticello, President Thomas Jefferson comments on an editorial recommending immediate succession from the Union.
April 8, 1803
A British alliance?
At a meeting of Jefferson‘s cabinet in Washington City, it is decided that an alliance with Great Britain regarding Louisiana should be pursued should negotiations to obtain that colony from France fail.
April 10, 1803
Napoleon renounces Louisiana
Napoleon decides to sell the entire Louisiana colony to the United States forever altering the history of the younger nation and a decision necessary for the success of Jefferson’s Western Expedition.
April 11, 1803
Talleyrand spills the beans
In Paris, Charles-Maurice de Talleyrand, tells U.S. Envoy Robert Livingston that Napoleon wants to sell the whole Louisiana colony. Napoloeon’s brothers try to change his mind.
April 14, 1803
Priced too high
In a letter to Thomas Jefferson written on this day, the American minister to France, Robert Livingston reports that the asking price of 125 million francs for the Louisiana Territory is too high.
April 17, 1803
Livingston's commission
In Paris, Robert Livingston asks for a better commission to negotiate the purchase of Louisiana. In Washington City, the U.S. Attorney General writes questions for Lewis to ask of the Native Nations.
April 18, 1803
Ellicott's instruments
In Lancaster, Andrew Ellicott writes about navigational instruments he believes are for Meriwether Lewis. In Washington City, James Madison writes an alternate plan for the Louisiana negotiators.
April 19, 1803
New Orleans re-opens
James Madison receives news that the Spanish King has opened the port of New Orleans to United States merchants. Meanwhile, Meriwether Lewis completes his work at the Harpers Ferry armory.
April 27, 1803
Philadelphia mentors
Jefferson tells Lewis of the mentors waiting for him in Philadelphia and informs the public that the expedition is headed to the Mississippi. In Paris, the price for Louisiana’s purchase is negotiated.
April 29, 1803
The price for Louisiana
In Paris, France, the Louisiana Purchase negotiators settle on a price—80 million francs plus payment of French debts worth about 20 million francs.
May 1, 1803
Monroe's presentation
James Monroe is presented to Napoleon and wordsmithing of the Louisiana Convention continues. Secretary of State James Madison writes a letter telling of imminent war between Britain and France.
May 2, 1803
Louisiana Treaty signed
The French-language version of the Louisiana Purchase Treaty and Convention is signed in Paris, France, and Robert Livingston writes to President Thomas Jefferson to tell him the news.
May 4, 1803
Pinckney's dead end
Minister to Spain, Charles Pinckney, writes from Madrid with news that the King will not concede any part of Florida, and that he defers the question of keeping the port of New Orleans open to France.
May 12, 1803
Dinner with Armistead Mason
Meriwether Lewis dines with Armistead Mason and other young Philadelphian gentlemen and ladies. In Paris, Robert Livingston reflects of the significance of the recently signed Louisiana Treaty.
May 13, 1803
Louisiana Treaty completed
In Paris, France, Robert Livingston and James Monroe record the details of the Louisiana Purchase for James Madison. Also in Paris, B. G. É. L. Lacepède provides information about the Columbia River.
May 18, 1803
Tackle and Indian gifts
In Philadelphia, Israel Whelan buys Indian gifts and fishing tackle. Spain announces the retrocession of Louisiana and Washington City learns that the port of New Orleans has reopened to American trade.
June 2, 1803
Ratify quickly!
In a letter written in Paris, U.S. Minister to France, Robert Livingston advises President Jefferson to ratify the Louisiana Treaty and its Conventions quickly. Lewis continues preparing in Philadelphia.
June 9, 1803
Jefferson's surprise
In Washington City, Jefferson receives the news that France wishes to sell their entire Louisiana colony. In Philadelphia, Meriwether Lewis has a painted chest made to hold his scientific instruments.
June 22, 1803
Louisiana news and rumors
A Frankfort newspaper reports that Louisiana will be ceded to the United States and in Washington City, the National Intelligencer reports that the port of New Orleans has re-opened.
July 3, 1803
News from France
A letter announcing that the Louisiana Purchase Treaty has been officially signed reaches Washington City. President Jefferson writes to Henri Peyroux, the former commandant of St. Genevieve.
July 4, 1803
Jefferson's letter of credit
The news of the Louisiana Purchase is made public and President Jefferson issues Meriwether Lewis an open letter of credit to pay for supplies or passage should he meet any ships at the Pacific Ocean.
July 15, 1803
Pittsburgh arrival
Lewis arrives at Pittsburgh and immediately writes the President. In Washington City, Thomas Jefferson writes to Lewis with news of the Louisiana Purchase and information about the Columbia River.
July 17, 1803
Louisiana questions
While Lewis prepares for departure in Pittsburgh, President Jefferson sends out a list of questions about Louisiana for the upcoming Congressional debate on the Louisiana Treaty and Conventions.
July 19, 1803
Stoddard's new orders
Amos Stoddard given orders to establish an Army fort in preparation for the transfer of Louisiana and Jefferson’s Western expeditions. Meriwether Lewis is in Pittsburgh having the barge built.
July 27, 1803
Orders for Kaskaskia
Lewis is in Pittsburgh having a military barge built prior to departure down the Ohio River. From Washington City, orders are issued to lease land in Kaskaskia to build an American Army post.
August 10, 1803
Reflections on Louisiana
Meriwether Lewis is in Pittsburgh having a military barge built. In Williamsburg, Virginia, St. George Tucker writes his Reflections . . . supporting the Louisiana Treaty and Conventions.
August 12, 1803
New Orleans attitudes
Meriwether Lewis is in Pittsburgh having a military barge built prior to departing down the Ohio River. Elsewhere, a diplomat, U.S. Senator, and President Jefferson discuss the cession of Louisiana.
August 18, 1803
Louisiana cession news
Lewis is in Pittsburgh having a military barge built prior to departing down the Ohio River. President Jefferson in Monticello and Daniel Clark in New Orleans write news of the Louisiana cession.
August 31, 1803
Leaving Pittsburgh
After eight months of preparation, Lewis finally leaves Pittsburgh with a crew of eleven hands. During a stop, he shows off his new air gun, and Blaze Cenas accidentally shoots a female spectator.
September 20, 1803
Little and Big Guyandotte Rivers
Near the Guyandotte River, WV On or near this day, Lewis passes present-day Guyan Creek and speeds through a narrow section of the Ohio River perhaps anchoring near an “ugly” riffle at the mouth of the Guyandotte River. In New Orleans, its future governor promises the citizens an “inheritance of Freedom.”
September 29, 1803
Mastodon bones
Cincinnati, OH Lewis rests his boat crew and works with Dr. Goforth to examine the fossil bones that were excavated from nearby Big Bone Lick. The governor of the Mississippi Territory updates President Thomas Jefferson on the Louisiana Territory.
October 3, 1803
Spoiled smallpox vaccine
Cincinnati, OH Lewis writes a letter to President Thomas Jefferson. In it, he provides most of the information we have about his days in Cincinnati. He thanks Jefferson for sending a vaccine and asks the President to send a copy of the Louisiana Purchase treaty.
October 4, 1803
Traveling to Big Bone Lick
Big Bone Lick, KY On or near this date, Lewis leaves Cincinnati for the fossil diggings. There, he expects to collect specimens to send to Thomas Jefferson. Unfortunately, the owner of the site has ordered the removal of fossils stopped. Tensions rise between Spain and the United States over the Louisiana Purchase.
October 5, 1803
Big Bone Lick
Big Bone Lick, KY Lewis likely spent the day examining fossil bones. Thomas Rodney what he found there just five days later. The War Department asks the Army to prepare to fight with Spain over possession of Louisiana.
October 20, 1803
Louisville shipyards
Falls of the Ohio, KY-IN Two new recruits, Nathaniel Pryor and William Bratton, enlist. In Washington City, the Senate ratifies the Louisiana Purchase treaty.
October 24, 1803
Indian mounds
Falls of the Ohio, KY-IN Little is known about the activities of Lewis and Clark on this day. Perhaps the Indian mounds at Louisville piqued Lewis’s interest during his visit. In Washington City, debate resumes on the proposal to ratify the Louisiana treaty and conventions.
October 25, 1803
Last day at the falls
Falls of the Ohio, KY-IN This is the last full day Lewis and Clark spend at Louisville before heading to St. Louis. In Washington City, the House of Representatives ratifies the Louisiana treaty and conventions.
November 5, 1803
Shawneetown, Illinois
Shawneetown, IL One week ahead of the expedition, contemporary traveler Thomas Rodney finds wrecked boats below the Wabash River. In Washington City, the State Department prepares “An Account of Louisiana” for the press.
November 14, 1803
Mouth of the Ohio
Cairo, IL Lewis is ill, but he finds relief from a strong laxative found in Rush’s bilious pills. In Washington City, “An Account of Louisiana” is presented to Congress.
November 16, 1803
Seaman not for sale
Mouth of the Ohio, IL The captains scout the western shore of the Mississippi where a Shawnee Indian tries to buy Lewis’s dog, Seaman. In Washington City, Thomas Jefferson defines the boundaries of Louisiana and plans more expeditions.
November 18, 1803
Visiting Fort Jefferson
Mouth of the Ohio, IL The captains and eight men cross the Ohio to visit Fort Jefferson, started by William’s older brother, George Rogers Clark. Near Natchez, the Governor of the Mississippi Territory notices that Spanish officers are reluctant to cede Louisiana to France.
November 29, 1803
Spanish obstruction
Fort Kaskaskia, IL The captains are selecting more soldiers and making decisions about their next steps. While at Fort Kaskaskia, they learn the Spanish Governor of Upper Louisiana intends to block the expedition.
November 30, 1803
Spain cedes Louisiana
New Orleans, Louisiana Province Pierre-Clément de Laussat leads a procession of 60 Creoles through the rain to the Cabildo—the city’s seat of government—and signs papers officially transferring Spanish Louisiana to France.
December 3, 1803
Leaving Fort Kaskaskia
Ste. Genevieve, MO In the afternoon, Clark takes the barge three miles up the Mississippi River. Daniel Clark tells Secretary of State James Madison how the residents of New Orleans look forward to its cession to the United States.
December 7, 1803
Cahokia arrivals
Meramec River, MO to Cahokia, IL
Lewis traveling by land, and Clark by river, arrive at Cahokia. Lewis meets two useful locals, John Hay and Nicholas Jarrot who help him negotiate entering Spanish territory.
December 20, 1803
Louisiana's formal transfer
Winter Camp at Wood River, IL Clark uses the Commissary’s wagons to haul logs and by the end of day, the enlisted men move into their huts. In New Orleans, officials conduct the formal transfer of the city and lower Louisiana from France to the United States.
December 23, 1803
Uncertainties with Louisiana slaves
Winter Camp, Wood River, Illinois
Lewis investigates potential problems with the current French system of slavery and the future transfer of Louisiana to the United States. At Wood River, work continues building huts and a Lenape Delaware Indian known to Clark visits.
December 24, 1803
American emigrants
Winter Camp, Wood River, Illinois
Lewis finds that many American emigrants have arrived in anticipation of the Louisiana transfer. At winter camp, roofs are completed and passing boatmen visit with Clark.
December 27, 1803
Drying and storing blankets
Winter Camp at Wood River, IL Clark has blankets and other goods set out to air and dry before placing them in a storeroom. From New Orleans, William Claiborne and James Wilkinson report on Laussat’s opinion of the previous French boundaries of the Louisiana colony.
January 16, 1804
Shooting for the red leggings
Winter Camp at Wood River, IL Winter camp is re-supplied, a shooting contest with the locals is won by Reubin Field, and Clark receives a letter and other news from Lewis. In an address to Congress, President Jefferson announces Louisiana appointments.
January 17, 1804
River thick with ice
Winter Camp at Wood River, IL The temperature drops below zero, and Clark writes of nothing but the cold and thick river ice. In Washington City, Casa Yrujo proposes keeping American settlements east of the Mississippi River.
February 14, 1804
Lewis misses the ball
Clark attends a ball, likely in St. Louis, but Lewis remains at winter camp on the River Dubois to complete work. Elsewhere, Madison and Monroe debate the location of Louisiana’s northern boundary.
February 19, 1804
New Spanish orders
Wood River Camp, IL On or near this date, the Spanish Lieutenant Governor Dehault Delassus receives orders to transfer the Upper Louisiana Territory to Captain Amos Stoddard.
February 29, 1804
Skeptical federalists
Winter Camp at Wood River, IL A letter written by President Jefferson would have arrived in Cahokia by this date. The letter mentions the popularity of the expedition and the skepticism of the Federalists.
March 8, 1804
Announcing Louisiana's transfer
Wood River Camp, IL Lewis is in Cahokia with Captain Amos Stoddard and his honor guard who are traveling to St. Louis to formally receive the Upper Louisiana Territory. Clark is likely already there.
March 9, 1804
Lowering the Spanish, raising the French
Wood River Camp, IL Lewis serves as a witness to the delivery and receipt of the Upper Louisiana from Spain to France. With speeches and ceremony, the Spanish flag is lowered, and the French flag is raised.
March 10, 1804
Lowering the French, raising the American
Winter Camp at Wood River, IL U.S. Army Captain Amos Stoddard, acting as the representative of France, declares Upper Louisiana as belonging to the United States. The French flag, flying for only one day, is lowered and the American flag raised.
March 12, 1804
Informing the Indians
Winter Camp at Wood River, IL At the request of Capt. Stoddard and in the presence of Meriwether Lewis, Dehault Delassus delivers a speech to Indians informing them of the transfer of Upper Louisiana to the United States.
March 26, 1804
Finding Simon Girty
Lewis sends Thomas Jefferson Osage orange cuttings from Pierre Chouteau’s garden and in one of the Indian camps near the mouth of the Missouri, Clark meets Simon Girty, an infamous American traitor.
March 30, 1804
Casa Calvo's obstructions
At winter camp on the Wood River, the orders of yesterday’s military court are read. In New Orleans, Spanish Commissioner Casa Calvo asks that the Lewis and Clark Expedition be stopped by military arrest.
May 12, 1804
Expenses mount
Charles Gratiot forwards about $1500 in bills of expedition purchases. At winter camp, Clark arranges the boats’ loads. In Massachusetts, Samuel Brazer commemorates the Louisiana cession.
May 28, 1804
Drying wet cargo
At the Gasconade River, the expedition hunts and dries wet cargo. Having met with Captains Lewis and Clark on 25 May, trader Régis Loisel is now in St. Louis warning Spain of American encroachments.