David Thompson (30 April 1770 – 10 February 1857) was an Anglo-Canadian fur trader, surveyor, and cartographer, known to some native people as "Koo-Koo-Sint" or "the Stargazer".

Due to his widowed mother not having financial resources, she placed Thompson, 29 April 1777, the day before his seventh birthday,[4] and his older brother in the Grey Coat Hospital, a school for the disadvantaged of Westminster.

During those years he learned to keep accounts and other records, calculate values of furs (it was noted that he also had several expensive beaver pelts at that time even when a secretary's job would not pay terribly well), track supplies and other duties.

It was during this time that he greatly refined and expanded his mathematical, astronomical, and surveying skills under the tutelage of Hudson's Bay Company surveyor Philip Turnor.

[12] In 1790, with his apprenticeship nearing its end, Thompson requested a set of surveying tools in place of the typical parting gift of fine clothes offered by the company to those completing their indenture.

Thompson's decision to defect to the North West Company (NWC) in 1797 without providing the customary one-year notice was not well received by his former employers.

)[14] Thompson spent the next few seasons trading based in Fort George (now in Alberta), and during this time led several expeditions into the Rocky Mountains.

[15] He spent the next few seasons based there managing the fur trading operations, but still finding time to expand his surveys of the waterways around Lake Superior.

[11]: 35–38 After the general meeting in 1806, Thompson travelled to Rocky Mountain House and prepared for an expedition to follow the Columbia River to the Pacific Ocean.

[12] These posts established by Thompson extended North West Company fur trading territory into the Columbia Basin drainage area.

On reaching the junction Thompson erected a pole and a notice claiming the country for Great Britain and stating the intention of the North West Company to build a trading post at the site.

[11]: 103–110  This notice was found later that year by Astor company workers looking to establish an inland fur post, contributing to their selection of a more northerly site at Fort Okanogan.

On 14 July 1811, Thompson reached the partially constructed Fort Astoria at the mouth of the Columbia, arriving two months after the Pacific Fur Company's ship, the Tonquin.

[19] Before returning upriver and across the mountains, Thompson hired Naukane, a Native Hawaiian Takane labourer brought to Fort Astoria by the Pacific Fur Company's ship Tonquin.

[20] Thompson wintered at Saleesh House before beginning his final journey in 1812 back to Montreal, where the North West Company was based[11]: 124–130 .

[21] The years 1807-1812 are the most carefully scrutinized in his career and comprise his most enduring historical legacy, due to his development of the commercial routes across the Rockies, and his mapping of the lands they traverse.

He describes the party and some of the guests in his entertaining book The Shoe and Canoe, giving an excellent description of David Thompson: I was well placed at table between one of the Miss McGillivray's and a singular-looking person of about fifty.

His complexion was of the gardener's ruddy brown, while the expression of his deeply-furrowed features was friendly and intelligent, but his cut-short nose gave him an odd look.

I might have been spared this description of Mr David Thompson by saying he greatly resembled Curran the Irish Orator...[23]I afterwards travelled much with him, and have now only to speak of him with great respect, or, I ought to say, with admiration... No living person possesses a tithe of his information respecting the Hudson's Bay countries... Never mind his Bunyan-like face and cropped hair; he has a very powerful mind, and a singular faculty of picture-making.

He can create a wilderness and people it with warring savages, or climb the Rocky Mountains with you in a snow-storm, so clearly and palpably, that only shut your eyes and you hear the crack of the rifle, or feel the snow-flakes melt on your cheeks as he talks.

He settled in nearby Terrebonne and worked on completing his great map, a summary of his lifetime of exploring and surveying the interior of North America.

He began work on a manuscript chronicling his life exploring the continent, but this project was left unfinished when his sight failed him completely in 1851.

Meantime, Thompson's achievements are central reasons for other national historic designations: In 1957, one hundred years after his death, Canada's post office department honoured him with his image on a postage stamp.

[36] In 2007, a commemorative plaque was placed on a wall at the Grey Coat Hospital, the school for the disadvantaged of Westminster David Thompson attended as a boy, by English author and TV presenter Ray Mears.