The West Old & New Vol. III Issue III March 2014 | Page 10

cant survey, mapping a route to Lake Athabasca which straddles the Alberta/
Saskatchewan border.
In recognition of his map-making skills, the company promoted him to surveyor
in 1794. Thompson continued working for the Hudson's Bay Company until May 23,
1797 when, frustrated with the Hudson's Bay Company's policies, he left and walked
80 miles in the snow to enter the employ of the competition, the North West Company where he continued to work as a fur trader and surveyor.
His defection without providing the customary one-year notice was not well received by his former employers. However, joining the North West Company allowed
Thompson to pursue his interest in surveying and work on mapping the interior of
what was to become Canada. In 1797, Thompson was sent south by his employers to
survey part of the Canada-U.S. boundary along the water routes from Lake Superior
to Lake of the Woods to satisfy unresolved questions of territory arising from the Jay Treaty between Great Britain and the United
States. By 1798 Thompson had completed a survey of 6,750 km (4,190 mi) from Grand Portage, through Lake Winnipeg, to the
headwaters of the Assiniboine and Mississippi Rivers, as well as two sides of Lake Superior. In 1798, the company sent him to
Red Deer Lake, located in present-day Alberta to establish a trading post.
In 1804, at the annual meeting of the North West Company Thompson was made a full partner of the company and 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. However, a decision was made at the 1806 company meeting to send Thompson back out into the interior.
Concern over the American-backed expedition of Lewis and Clark prompted the North West Company to charge Thompson with
the task of finding a route to the Pacific in order to open up the lucrative trading territories of the Pacific Northwest.
David Thompson was the first European to navigate the full length of the Columbia River. During Thompson's 1811 voyage
down the Columbia River he camped at the junction with the Snake River on July 9, 1811, and 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.
David Thompson is known in Montana for having created a trading post in Thompson Falls, called Salish House. The building’s are gone now but every year the town of Thompson Falls holds David Thompson Days in July. It is a three day gathering of
people interested in the lifestyle of the fur traders, mountain man, and adventurer of the northwest.

Winter Hay in Camas Prairie, Montana photograph by S.F. Roberts
The West Old & New Page 10