Lewis leaves Lancaster and travels to Philadelphia to study medicine, anatomy and botany under the day's leading experts. During his three-week stay, he buys supplies and equipment as well as gifts for the Indians he expects to encounter.[7]
June 19
Lewis writes to William Clark inviting him to co-lead the expedition.[8]
June 20
President Jefferson sends Lewis instructions for exploring the Louisiana Territory.[9]
While the Corps camps at the confluence of the Ohio and Mississippi Rivers, Lewis and Clark practice determining longitude and latitude using their surveying instruments.[22][20]
Lewis travels by horseback to St. Louis in present-day Missouri intending to spend the winter procuring more supplies.[24][25]
December 12
Clark arrives at the site of the expedition's winter encampment on the Mississippi River above St. Louis in Illinois. The construction of Camp Dubois begins the next day.[26][27]
December 20
France transfers the Louisiana Territory to the U.S., which takes possession on December 30.[10]
1804
Date
Event
March 9
Lewis attends ceremonies in St. Louis witnessing the formal transfer of the new U.S. territory.[28][29]
March 26
To his bitter disappointment, Lewis learns that Clark's commission has been approved but as a lieutenant rather than captain. Despite the difference in rank, a fact withheld from the men, the two share command equally throughout the expedition.[30]
March 29
Pvts. Shields and Colter are tried for mutiny following a fight in which they threaten Sgt. Ordway's life. Their pleas for forgiveness are accepted.[31][32][33]
March 31
Lewis and Clark hold a ceremony formally inducting 25 recruits into the Corps. Another five men are designated to return on the keelboat the next spring before the "permanent party" crosses the Rocky Mountains.[34][35]
April 7
Lewis and Clark travel to St. Louis by canoe to attend a dinner and ball.[36][37]
Pvts. Collins, Hall and Werner are court martialed for being AWOL. Collins, who is convicted of additional charges, receives 50 lashes. The other two have their sentences of 25 lashes suspended.[43]
May 21
With Lewis and Clark in command, the Corps embarks on the keelboat and two pirogues. During their 2,300 mile trip to the Rockies, the men struggle against the Missouri's current. While sails help when the winds are favorable, most progress is by rowing and either pushing or pulling the heavily ladened keelboat.[44][45]
May 25
About 50 miles from St. Charles, the party passes La Charette, the westernmost Euro-Americansettlement on the Missouri.[46]
June 26
The expedition encamps at Kaw Point near the Missouri's confluence with the Kansas River in present-day Kansas, 400 river miles into their journey. As a precaution against a possible attack by the regions's Kansa tribe, the men build a temporary defense, but otherwise they spend several days resting and repairing their boats.[47][48]
June 29
During the Corps' stay at Kaw Point, Pvt. Collins is court martialed on charges of stealing whiskey while on guard duty. His sentence is severe, 100 lashes. Pvt. Hall, who is tried for drinking with Collins, receives 50 lashes.[49][48]
The Corps enters present-day Nebraska. Pvt. Willard is caught sleeping on guard duty, a capital offense. He is sentenced the next day to receive 100 lashes in four equal installments.[52]
The Corps camps near today's Fort Calhoun, Nebraska, on a hill they name Council Bluff.[56]
August 3
Lewis and Clark meet at Council Bluff with chiefs of the Oto and Missouri tribes. While the chiefs want weapons more than token gifts, the Corps' first attempt at diplomacy is for the most part a success.[57][58]
August 4
The party departs, but Pvt. Reed deserts. Two days later, the captains determine Reed is to be brought back dead or alive.[59][60]
August 18
Reed is captured and returned for trial. In addition to being sentenced to a flogging in which he is required to run the gauntlet four times, Reed is expelled from the Corps. Since banishment to the wilds would be a death sentence, he is allowed to remain with the expedition through the winter.[61][62]
August 20
Sgt. Floyd dies, probably from a ruptured appendix. He is the sole casualty of the two-year expedition.[63][64]
August 26
The men elect Pvt. Gass sergeant. Pvt. Shannon, the Corps' youngest member, becomes lost while searching for horses stolen by the Indians.[65][66]
Lewis and Clark hold talks with the Yanktons, who want rifles and whiskey. Instead, the tribe is invited to send a delegation to meet with the Great White Father in Washington, D.C.[68][69][70]
September 11
Pvt. Shannon is found on the bank of the Missouri starving and out of ammunition after being lost 16 days.[71]
September 20
They reach the Missouri's Big Bend in central South Dakota, nearly 1,300 miles from their starting point.[72]
September 25
Weapons are drawn in a confrontation with the Lakota Sioux near modern-day Pierre, South Dakota. Elder Chief Black Buffalo diplomatically intervenes, averting bloodshed.[73][40][70]
October 13
Pvt. Newman is convicted of mutinous talk and expelled. As with Pvt. Reed, he is permitted to remain with the expedition until the spring.[74][75]
October 24
The Corps reaches Mandan Indian territory near present-day Washburn, North Dakota. Over the next few days, they meet with Mandan and Hidatsa chiefs and begin looking for a site for a winter fort.[76]
November 2
A location for their winter fortification is selected across the river from the main Mandan village. They name the encampment Fort Mandan to honor the tribe. Construction begins.[77]
The Corps celebrates Christmas with special food, rum and dancing.[81]
1805
Date
Event
February 9
Pvt. Howard returns after dark and scales the fort's wall instead of asking the guard to open the gate. An Indian happens to see this and scales the wall himself. In the last disciplinary trial of the expedition, Howard is charged with a breach of security and is ordered to receive 50 lashes, but Lewis suspends the sentence.[82]
With the arrival of spring, the Corps resumes its journey. The keelboat is sent back down the Missouri with a crew of a dozen men and a shipment for President Jefferson. The "permanent party" travels west in the two pirogues and six dugout canoes.[84]
April 25
The expedition reaches the confluence of the Yellowstone River in northwestern North Dakota, the Missouri's principal northern tributary.[85]
April 27
They enter present-day Montana. In the ensuing days, the men sight herds of up to 10,000 buffalo. They also encounter and kill their first grizzly bear.[86]
May 14
A sudden storm tips a pirogue and many items, including the Corps' journals, spill into the river. Sacagawea calmly recovers most of the items, earning Clark's praise for her quick thinking.[87]
May 26
Lewis sees the Rocky Mountains for the first time. His initial reaction is joy, but he then considers the serious challenges the snow-covered mountains will pose for his men.[88]
June 1
In north-central Montana, the Corps comes to an unexpected fork in the river, with one branch flowing from the north, the other from the south. They take a vote on which is the Missouri. Only Lewis and Clark favor the southern route. After days of debate and explorations, another vote yields the same result. Despite their doubts, the men agree to follow the leaders.[89]
June 13
A scouting party led by Lewis reaches the Great Falls of the Missouri. The discovery proves they have taken the correct course.[90]
June 17
The men circumnavigate the falls, dragging their canoes and equipment across 18 miles (30 km) of rough terrain, a month-and-a-half ordeal.[91]
August 8
Sacagawea recognizes a natural formation from her childhood, Beaverhead Rock, indicating they are in the area where the Shoshone spend their summers.[92]
While Clark is on a scouting expedition, Lewis meets up with sixty warriors of the Shoshone nation. Once he establishes their peaceful intentions, he and his men are welcomed into the tribe's village.[94]
August 16
When the Shoshone become fearful of being led into a trap, Lewis lends his rifle to the Chief and his men follow suit. The gesture helps gain the Shoshone's trust.[95]
August 17
Sacagawea has a tearful reunion with her brother Cameahwait, now a Shoshone chief. Clark returns, and with Sacagawea's help, the Corps is able to negotiate for the horses needed to cross the Rockies.[96]
September 4
The expedition approaches the eastern slope of the Bitterroot Mountains and enters a valley near Sula, Montana. They are met by a band of Bitterroot Salish, also known as Flathead Indians, and spend two days resting and trading for horses. The band consists of 33 lodges, 80 men, and 400 total members.[97]
September 11
After several days at Traveler's Rest near Lolo, Montana, the Corps begins crossing the Bitterroot Mountains, the most dangerous leg of the entire journey. Over the next 11 days, the men struggle through deep snow. Starving, they resort to eating some of their colts.[98]
September 22
Emerging from the mountains on the Weippe Prairie, the expedition is taken in by the Nez Perce Indians. In the days ahead, everyone becomes sick from overeating the dried fish and boiled roots served by their hosts.[99]
September 26
The party travels down north central Idaho's Clearwater River to set up an encampment for building canoes, west of present-day Orofino. Work proceeds slowly as the men recover.[100]
The Corps reaches the Columbia at present-day Tri-Cities. Several miles to the south, the Columbia turns west and is the modern-day border of Oregon and Washington.[103]
October 18
Clark sights Mount Hood through the fog, some 45 miles (72 km) in the distance.[104]
October 22
The Corps descends Celilo Falls, the beginning of a treacherous 55-mile (90 km) stretch of the Columbia.[105][106]
November 7
Clark writes in his journal, "Great joy in camp we are in View of the Ocian". His elation is premature. They have sighted the Columbia River's estuary and are still twenty miles (30 km) from the Pacific.[107][108][109]
November 8
The waves in the estuary become too hazardous for the canoes, so they set up camp.[110]
November 10
The men attempt to make progress by hugging the shoreline, but the dangerous conditions again force them to shore.[111][112]
November 12
A violent thunderstorm strikes with hail, heavy rain, and gale force winds. After burying all but one of their canoes under rocks to prevent them from being crushed by the waves and floating logs, they retreat by land to a cove up river. They are pinned down here for several days as the inclement weather continues.[113][114][115]
November 15
With a break in the weather, the estuary becomes navigable, enabling the Corps to reach the Pacific. The men land on a sandy beach that they name Station Camp. They spend the next ten days here hunting, trading with the Chinook and Clatsop Indians, and exploring the surrounding coastline.[116][117][115]
November 24
The Corps' members vote on a site for their winter encampment. Sacagawea and York, Clark's slave, participate in the vote. Following the recommendations of the local Indians, they pick a site on the south side of the river (Oregon), where game is more plentiful.[118]
The expedition's log fortress is completed, but the winter proves miserable as it rains during all but twelve days of their three-month stay.[120][121][122]
1806
Date
Event
March 23
The Corps departs Fort Clatsop, eager to begin their journey home.[123]
April 18
The expedition reaches the Columbia's Great Falls. They need horses for re-crossing the Rockies, but the Native Americans demand steep prices so they buy only four.[124]
April 28
They leave Oregon, following the Columbia to the Snake River in southeastern Washington.[125]
May 3
After enduring a heavy snow storm, the Corps meets up with a familiar Nez Perce chief and 10 of his men.[126]
May 5
The expedition reaches present-day Idaho, where they pick up the Clearwater River.[127]
May 14
Having started their journey too early, the Corps must wait for the mountain snows to melt. The men camp for nearly a month in what is now the Nez Perce Reservation.[128]
June 10
They pull up camp and four days later reach the Bitterroot Mountains.[129]
June 24
The Corps starts to cross the Bitterroots. With the help of three Nez Perce guides, they cut 300 miles off the journey.[130]
June 29
The expedition enters western Montana through Lolo Pass.[131]
July 3
The Corps is divided in two to enable them to explore additional lands. Lewis leads one group down the Missouri, while Clark's takes a southern route following the Yellowstone River. Along the way, they break into smaller exploratory groups.[132][133]
July 25
Clark names a rock formation on the Yellowstone for Sacagawea's son, a site now known as Pompeys Pillar. Clark inscribes his name and the date on the rock face, the only remaining physical evidence of the Corps' journey.[134]
July 26
Traveling on horseback, Lewis and his men encounter a small band of Blackfeet warriors. They spend the night together, but in the morning two Blackfeet braves are killed while trying to steal the group's guns and horses. Afraid of reprisals, the men ride for nearly 24 hours.[135]
August 2
Clark's group reaches the Missouri and enters present-day North Dakota.[136]
August 11
Lewis is accidentally shot in the buttocks by one of his men.[137]
August 12
The Corps reunites on the Missouri in western North Dakota near the mouth of Knife River.[138]
August 14
The expedition returns to a warm welcome by the Hidatsa and Mandan tribes.[139]
August 17
The men continue down the Missouri, leaving Charbonneau, Sacagawea and their son with the Mandans. Clark offers to raise the boy, who is now 19 months old. With the Missouri's current in their favor, they are able to cover over 70 miles a day.[140]
September 23
The Corps arrives in St. Louis, successfully concluding their 8,000-mile journey after two years, four months and 10 days.[141]
December 28
Lewis arrives in Washington, D.C. At the end of February, Jefferson nominates him as Governor of Upper Louisiana.
1807
Date
Event
January 15
Clark arrives in Washington, D.C. He is appointed Agent for Indian Affairs in the Louisiana Territory.
^Rees, Mike (May 2009). "Ocean in View?"(PDF). We Proceeded On. 35 (2). Great Falls, Montana: Lewis and Clark Trail Heritage Foundation: 22–30. Retrieved February 16, 2020.
^ abZiak, Rex (May 2005), "Seven Days on the Lower Columbia"(PDF), We Proceeded On, 31 (2), Lewis and Clark Trail Heritage Foundation: 10–19, retrieved March 18, 2020{{citation}}: CS1 maint: date and year (link)
