Start of the Lewis and Clark Expedition

Captain Meriwether Lewis set off from Pittsburgh on 31 August 1803, to begin the first American expedition to the Pacific overland.

A map of Lewis and Clark's track across the western portion of North America, from the Mississippi to the Pacific Ocean : by order of the executive of the United States in 1804, 5 & 6. Library of Congress.

Captain Meriwether Lewis, aged twenty-nine, set off from Pittsburgh by boat at the end of August with a party of men and his Newfoundland dog, Seaman, to begin the first American expedition to the Pacific overland (Andrew Mackenzie had crossed Canada to the Pacific in the 1790s). At Louisville he picked up his chosen co-leader, Lieutenant William Clark, who was four years older. The two men, both from uppercrust Virginia planter families, had become friends in the army. Lewis had been personal assistant to President Thomas Jefferson, who authorised the expedition to find a water route through the Rocky Mountains to the west coast, make friendly contact with the native Indians and report on matters of scientific interest. One underlying motive was the hope of opening up a trade route to the Far East, far shorter than the voyage round the Horn. The fact that much of the territory to be explored belonged to Spain was not considered a deterrent.

Though interested in natural history, the two leaders were not intellectuals, and certainly neither of them could spell, but they had more valuable qualities. They were army officers, decisive practical men, resourceful leaders and man managers, experienced at dealing with Indians and coping with wild country and danger. Clark was the more outgoing and adventurous of the pair, Lewis the quieter, prone to bouts of depression.

The expedition spent the first winter training in camp near St Louis. In May 1804 the ‘corps of discovery’ of more than forty men, mostly soldiers, with Clark’s black servant and the dog, set out in pelting rain and what Clark described as ‘a jentle brease’ in three boats propelled by sail and oars – a 55ft keel-boat and two smaller pirogues. They moved slowly up the Misssouri River into today’s North Dakota, which they reached at the beginning of November after a tense, though bloodless, encounter with a Sioux chief called Black Buffalo and his band. The expedition spent the next winter amicably with the Mandan Indians. The keel-boat was too big to go any further, so they built themselves dugout canoes. Heading for Shoshoni territory, they were able to enlist a Shoshoni woman named Sacagawea (‘Bird Woman’) as guide and interpreter. She had been carried off in 1800 in an Indian raid and sold to a French Canadian fur trader called Charbonneau, who went along too. Sacagawea gave birth to a boy on the journey and Clark wrote that ‘A woman with a party of men is a token of peace.’

The expedition left in April 1805 to travel on up the Missouri to the Jefferson River, as they named it, which they followed south-west to the Shoshoni, who sold them horses and provided squaws as porters. On horseback they pressed on through the Rockies to the country of the Nez Percé, where they built themselves another fleet of dugout canoes and travelled down the Clearwater, the Snake and the Columbia, surviving rocks and rapids, to reach the Oregon coast and the Pacific in November 1805. ‘Great joy in camp,’ Clark recorded. ‘We are in view of the Ocian, the great Pacific Ocian which we have been long so anxious to see.’

They built a wooden fort close to present-day Astoria and spent a wet winter there. The local Indians’ use of phrases like ‘heave the lead’ and ‘son of a pitch’ showed that Yankee ships had visited the area and the expedition hoped to go back home by sea, but no ships turned up, so they returned overland. They set off in March 1806 and split into two parties to explore different routes, Clark’s party going down the Yellowstone. Lewis’s group’s skirmish with Blackfoot Indians was the only fighting the expedition did on the entire journey. The groups reunited near the Yellowstone-Missouri junction and reached St Louis on September 23rd, 1806, to be greeted as heroes after travelling 8,000 miles through country almost totally unexplored by whites.

Only one member of the expedition died, possibly of a ruptured appendix. Everyone else and the dog returned safely. Creatures they discovered that were previously unknown to whites included the grizzly bear, ‘a most tremendious looking anamal’ as Lewis recorded. They did not find a water route to the Pacific – there wasn’t one to find – but they pioneered the Oregon Trail, collected an immense amount of useful information and paved the way for the American conquest of the West.

The two men’s journals of the trip were published in 1814 after Lewis, sent back to St Louis as governor, had died in 1809, aged thirty-five, either of suicide or foul play. Clark became governor of Missouri and died in 1838, aged sixty-eight.