David Thompson was possibly the greatest explorer of the continental interior of North America .  He is widely known throughout Canada for his accomplishments, although is virtually unknown in the United States.  He had a passion for exploration and was a skilled surveyor and navigator.  As an employee of the Hudson's Bay Company, and later as a wintering partner for the North West Company, David Thompson traveled some fifty-five thousand miles by foot and canoe across the interior of North America.  Maps prepared by David Thompson filled in the geographic gaps on nearly two million square miles of Canada west of Hudson’s Bay, and portions of what is now north-central and northwestern United States.  David Thompson and his men erected the first trading establishments west of the Continental Divide in Washington, Idaho, and Montana.  He opened the first trade with the northwestern Indian tribes of the United States and Lower Canada . 

David Thompson was born in Westminster, England, April 30, 1770 . His father died when David was two years old. At age 7 he was enrolled in the Grey Coat School near Westminster Abbey, a charity school aimed to educate poor children in the principles of piety and virtue.  He spent seven years there and received a basic education including geography, algebra, and navigation.  His education was preparing him for service in the Royal Navy, however, the American Revolutionary War ended before he graduated.  He probably would have found a career in the merchant marine, however, the Hudson's Bay Company contacted the school's headmaster about recruiting apprentices to serve in the North American fur trade.  At age fourteen he started his apprenticeship as a clerk.  In September of 1784 he arrived at Churchill Factory on Hudson Bay.  His first two years as a Hudson’s Bay Company employee were spent at the Churchill and York factories before being stationed at several posts on the Saskatchewan River.

Thompson spent the winter of 1787-88 on the Bow River not far from present day Calgary.  In December of 1788, David Thompson fell down a steep creek bank and broke his leg.  The break was so severe that for sometime it was feared that it would be necessary to amputate his leg.  After spending several months at Manchester House on the North Saskatchewan, he was sent downriver to Cumberland House, which was the first interior trading post built by the Hudson's Bay Company.  Cumberland House was located on the Saskatchewan River near Lake Winnipeg .

During his convalescence at Cumberland House, Thompson met Philip Turnor, the Hudson’s Bay Company astronomer.  Turnor was planning a surveying expedition to the Athabasca country.  Throughout the remainder of the winter, Turnor tutored Thompson in surveying and practical astronomy.  During this training, Thompson lost the sight in his right eye, probably from staring at the sun.  Although Turnor needed an assistant, Thompson was not selected because his leg was still too weak.

Surveying and mapping became David Thompson's passion.  When his apprenticeship expired, Thompson signed on for another seven years with the Hudson's Bay Company.  It was customary for the Hudson’s Bay Company to providing re-enlisting men a suit of clothes.  Instead of the clothes, Thompson requested that the Company furnish him with a compass, watches, thermometers, sextant, an artificial horizon, and Nautical Almanacs.  The management of the Hudson's Bay Company was so pleased with Thompson's work that they provided him with everything he requested plus the new suit of clothes.  With his new instruments, Thompson spent the next several years exploring and trading around York Factory and in northern Manitoba and Saskatchewan.   

David Thompson apparently became dissatisfied with the Hudson’s Bay Company, because its emphasis on the fur trade didn’t allow him time to pursue his interests in exploration and surveying.  On May 21st, 1797, he informed his supervisor, Malcolm Ross, that he intended to leave the service of the Hudson's Bay Company.  In those times it was company policy that one years notice be given so that a replacement could be appointed and moved into position.  Thompson's unhappiness is apparent in that he left the next day.  He immediately received employment with the North West Company.  He arrived at the that company's headquarters at Grand Portage on Lake Superior in July of 1797.                              

One of Thompson’s first assignments was to determine the precise location of posts belonging to the North West Company that might be affected by the Jay Treaty of 1794.  This treaty required that British fur companies respect the United States boundary as established by the Treaty of Versailles at the end of the Revolutionary War.  Enforcing this treaty was difficult because the precise locations of the boundary and the posts were uncertain in the wilderness of what was then described by the United States as the Northwest.

In November of 1797, David Thompson set out with nine men, first to pay a good will visit to the permanent location of the Mandan villages on the Missouri River.  These villages as well as those of the, Hidatsa, and Arikara were the site of trade fairs between the Plains Indians and both the Hudson’s Bay and North West fur traders.  From the Mandan villages, he proceeded eastwards to Turtle Lake, which he determined to be the headwaters of the Mississippi River…the actual head was later determined to be a few miles away.  He then surveyed the south shore of Lake Superior to Sault Ste. Marie, and then mapped the east and most of the north shores of Lake Superior before arriving at Grand Portage in June of 1798.  In ten months, David Thompson had mapped close to four thousand miles.  Based on his survey, he found that a number of North West Company trading houses were south of the border with the United States as was the North West Company headquarters at Grand Portage.  Shortly afterward the headquarters was moved inland to Fort Kaministiquia (Thunder Bay, Ontario). The fort was renamed Fort William in 1807.

David Thompson's map was to become an important resource for the Lewis and Clark Expedition, especially that portion covering the area of the Mandan Indian villages on the Missouri River.  Prior to their departure, Lewis and others did considerable research for any information regarding the wilderness into which they were to depart.  A tracing from Thompson’s map showing the Great Bend of the Missouri is on display in the Library of Congress.  There is a notation on the front of the map in President Jefferson’s hand reading: “Bend of the Missouri, Long. 101° 25' Lat. 47° 32' by Mr. Thomson astronomer to the N.W. Company in 1798.”

David Thompson married Charlotte Small on June 10, 1799.  She was the mixed-blood daughter of a North West Company partner, Patrick Small and his Indian wife.  At this time David was 29 whereas Charlotte was not quite 14.  Charlotte frequently accompanied him on his travels into the wilderness.  Together they would eventually have 13 children.  

Thompson excelled at everything he did, and by 1799 he was one of the better paid clerks in the company, earning one hundred pounds per year plus twenty pounds worth of equipment and necessities such as clothing, tea, sugar, and chocolate. 

In 1801 Thompson attempted to find a more southerly route to the Pacific Ocean then that discovered by Mackenzie in 1793.  Mackenzie’s route was too far to the north to be practical as a transportation route for the fur trade.  This first attempt to find an alternate route by Thompson would not be successful.  

From 1802 to 1806, Thompson was responsible for the fur trade between the Peace River and Churchill River areas.  At it’s annual meeting at Fort Kaministiquia in 1806, the North West Company partners promoted Thompson to a wintering partner of the company.  At this time the partners decided to make another attempt to find a more southerly route to the Pacific Ocean . 

On May 10, 1807, the David Thompson family, Finan McDonald, and eight voyageurs traveled up the North Saskatchewan River, past the Kootenay Plains, and over what would later come to be known as Howse Pass.  They descended the Blaeberry River to a large north flowing river.  Because the river flowed north, Thompson was not sure that it was the Columbia …from its source at Columbia Lake, the Columbia River flows five hundred miles north along the base of the Canadian Rocky Mountains before it turns back and runs south and west to the Pacific Ocean.  Going south up the river, they stopped at Lake Windemere and built Kootanae House.

The following spring (1808), David Thompson left Charlotte and the children at Kootanae House and crossed over to the Kootenay River.  His plan was to explore the Kootenay River as well as find the Flathead Indians (Salish).  He followed the Kootenay River into Montana, Idaho, and back into Canada before crossing back over to Kootanae House.  Among other items, Thompson traded guns to the Flatheads, Kootenais and other tribes further to the west.  Because of this trade in firearms, the posts he established along the Rockies would have difficult relations with the Blackfoot and Piegen Indians, who resented the end of their dominance in the region resulting from the trade in firearms to their enemies.

After returning the furs in 1808 to the North West depot at Rainey Lake and again in 1809 to Fort Augustus near present day Edmonton, David Thompson returned to winter at Kootanae House.

Accompanied by a number of men, including Jaco Finlay and Finlay's family, he went to Pend Oreille Lake in Idaho where they built Kullyspell House.  Thompson spent the remainder of the fall and early winter exploring in the vicinity, and ended the year by establishing Saleesh House on the Clark Fork River near modern day Thompson Falls, Montana.

In the spring of 1810, David Thompson made a number of explorations in vicinity of the Saleesh and Kullyspell houses.  That May, he left to again take his furs over Howse Pass to the North West Company depot at Rainy Lake.  While there, Thompson learned that John Jacob Astor had dispatched a ship and an overland party to the mouth of the Columbia River.  At this time the North West Company was considering a purchase of a one-third interest in Astor's venture. 

Astor’s plans for trade at the mouth of the Columbia River gave new urgency to the North West Company to trace the Columbia River to it’s mouth and to establish a new supply route.  The supply route from the Columbia River Basin posts to the North West Company depots was too long to be competitive with posts supplied by sea and then up the Columbia River.  Horses and canoes were used to transport the furs from Spokane House, Saleesh House, Kullyspell House, and Kootanae House over the mountains, down the Saskatchewan and on to Fort William, and from there by canoe to Montreal.  From the locations of his Columbia River Basin posts and the surveys of Lewis & Clark, David Thompson knew it was not far to the mouth of the Columbia River.  With a post at the mouth of the Columbia River, ships could be used to transport the furs and trade goods, and thus eliminate the long supply route across most of the North American continent.  While at the Rainy Lake rendezvous, Thompson was directed by the North West Company to renew his efforts on establishing a link down the Columbia River to the Pacific Ocean while continuing his other trading responsibilities. 

David Thompson and several men headed back toward the Columbia River Basin in four canoes.  Earlier in the year a hunting party of Flatheads had gone to the Montana plains to hunt buffalo, and in a fight with a party of Piegans (Blackfeet), seven Piegans were killed and thirteen wounded whereas only five Flatheads were killed.  This was a major victory by the Flatheads over their Blackfoot enemies and a represented major shift in power.  The Blackfoot blamed their defeat on the arms and ammunition provided by Thompson to the Flatheads, Kutenai and Nez Perce.  The Blackfeet were determined to block Howse Pass and not to let the white traders into the Kootenay country again. 

With Howse Pass blocked, David Thompson determined to attempt an alternative route, much farther north than the Piegans normally ranged, over a pass near the headwaters of the Athabasca River.  Pioneering a new route so late in the season was very unusual, but Thompson had little choice because he had the exploration for the Columbia River to complete, and also men at three trade houses waiting for supplies.  After pausing to make dog sleds and snowshoes (click here for more information about dog sleds), Thompson’s party, set off on October 29th, for the Athabasca Valley.  It is interesting to note what Thompson's party took with them.

"Gave the Men their Loads for the Sleds--each Sled that has 2 Dogs, B. D'Eau, Coté, Francois, & L'Amoureux have 120 lbs of Goods & Necessaries for the Journey, & Vallade, Battoche, Pareil & Du Nord each 1 Dog & Sled have 70 lbs per Sled.  4 Horses loaded with Meat, having 208 lbs of Pemmican, 35 lbs of Grease & 60 lbs of Flour also accompany us to ease the Dogs".  On January 6th, they left the horses because of the poor trail and lack of feed, and on January 24th, Thompson cached some of his trade goods. "Part of the Things in the Hoard are 3 fine Capots, 4 do Shirts, 12 lbs of Beads, Garden Seeds, 8 groce of Rings, 3 Rolls of Ribbon, 6 groce of Bells, 3 Jockey Caps, 4 Cotton Shirts, 1 pr of Cloth Trowsers DT, 3 doz Glasses, 6 Bott[les] of Turlington, 1 Roll of Gartg, 2 Bott[les] of Peppermint, 6 Worms, 6 Steels (Baylea)."

David Thompson crossed the mountains through Athabasca Pass (near today's Jasper, Alberta).  Deep snows, sub-zero temperatures and shortages of food made travel extremely difficult.  Even caching a large part of the goods didn't improve progress and at the forks of the Canoe River and the Columbia River, his men refused to go on, and he was forced to spend the winter.

In the spring of 1811, David Thompson's party started construction of a canoe to haul their goods and supplies on the river.  Unable to find birch bark, they constructed a twentyfive-foot clinker-built (overlapping boards) canoes out of cedar.  The party went up the Columbia River to Kootanae House and then, portaged to the Kootenay River and floated down it.  Saleesh House and Kullyspell had both been abandoned because of the Piegan threat.  Leaving the river, Thompson went to Spokane House, which had been built the year before by Jaco Finlay.  Going on to Kettle Falls, he and five voyageurs, two Iroquois and two Sanpoil Indian interpreters started down the Columbia River.

At the junction on the Columbia and Snake rivers, David Thompson stopped and planted a pole with a note on it: “Know hereby that this country is claimed by Great Britain as part of its territories and that the N.W. Company of Merchants from Canada do hereby intend to erect a factory."  The party reached the mouth of the Columbia on July 15, 1811; three months after the Tonquin, a sailing ship belonging to the American Fur Company, had arrived and started building Astoria.  When Thompson's party arrived, a post with a warehouse to store goods and furs had been constructed, and the Astorians were getting ready to send a party up river to initiate trade with the Indians.  

Thompson's party was received on friendly terms by the Astorians.  Although in the employ of the American Fur Company, all of the Astorians were Canadian, and many were former North West Company men as well.  Although both groups of men had much in common, neither party was entirely forthcoming about their full intentions.  The deal whereby the North West Company was to purchase a one-third interest in Astor's venture had fallen through several months previously.  In addition, tensions were high between Britain and the United States in this period immediately before the start of the War of 1812, and the Astorians knew they were in a very vulnerable position. 

After a week of being wined and dined at Astoria by Duncan McDougall, Thompson went back up the Columbia with David Stuart, Alexander Ross, and seven other Astorians.  Leaving the Astorians on the last day of July, Thompson and his men continued up the Columbia to their winter camp on the Canoe River.  When he reached his previous winter camp, David Thompson had traveled the entire course of the Columbia River.

With supplies that had been brought over Athabasca Pass, Thompson returned to Spokane House, and then proceeded overland to rebuild Saleesh House for the winter. A week after his party arrived there, John McTavish and James McMillan arrived with a group of fifteen men on their way to Astoria. 

In August 1813, Astoria was "captured" by men of the North West Company.  A token sum, approximately one-third value, was paid to Astor by the North West Company for the fort and its contents, and approximately forty thousand dollars was allowed for furs worth upwards of one hundred thousand dollars.  Many of the Astorians rejoined their former company.  Two months later, the British war ship, Raccoon, arrived on the Columbia and would have captured Astoria as a prize of war had it not already been sold to British interests. Astoria was renamed Fort George, and it remained a North West post until the 1821 merger of the North West and Hudson’s Bay Companies.  After the Hudson's Bay Company built Fort Vancouver (1825) on the north shore of the Columbia River, across from the mouth of the Willamette River, Fort George was abandoned.

David Thompson left the Columbia River Basin in the spring of 1812 and was back at Fort William by August.  Retiring from the North West Company, he was allowed his share of the North West Company profits for the next three years.

Thompson and his wife, Charlotte, moved to Terrebonne, a community north of Montreal.  Here he was appointed to the commission that surveyed the boundary between Canada and the United States following the war of 1812.  Thompson's measurements were generally accepted by both Canada and the United States.

With the merger of the North West Company and the Hudson's Bay Company in 1821, both Thompson and his work were treated with indifference.  Governor George Simpson, one of the upper level managers in the Hudson's Bay Company, turned Thompson's survey data over to mapmaker Aaron Arrowsmith of London.  Thompson was not given any credit for his data that was used on the Arrowsmith maps.

Despite retiring relatively wealthy, financial reversals and poor investments left David Thompson in poverty and virtual obscurity, with little credit for his accomplishments .  Although fame and wealth would elude him in his later years, he maintained close ties with his children and grandchildren.  At age 75 he immersed himself in writing his "Narrative", the story of his life and experiences in the fur trade.  David Thompson died on February 10, 1857 near Montreal. Charlotte would die three months later.  They are buried side by side in Montreal's Mount Royal cemetery.

The unfinished "Narrative" was sold unpublished, and then forgotten.  Thirty years after Thompson's death, J.B. Tyrrell, a Canadian geologist was plotting information on some amazingly accurate old maps.  After he determined who had drawn the maps, Tyrrell researched the original reports of David Thompson.  He located and purchased the four unfinished draft copies of the "Narrative" and then put together a manuscript which was published in 1916 by the Champlain Society.  

For more information about David Thompson see the following references:

David Thompson: Narrative of his Explorations in Western North America, 1784-1812, Tyrrell, J.B. ed, published by the Champlain Society, Toronto, 1916.

Sources of the River: Tracking David Thompson Across Western North America, Jack Nisbet, published by Sasquatch Books, 1994.  

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