"David Thompson, fur trader, explorer, surveyor, mapmaker (b at London, Eng 30 Apr 1770; d at Longueuil, Canada E 10 Feb 1857). Apprenticed to the HUDSON'S BAY CO in 1784, Thompson devoted most of his life to the study of geography and the practice of mapmaking." Read More...
Source: Nicks, John, S. "David Thompson." The Canadian Encylopedia. Historica Dominion, 2011. Jan. 27, 2011. http://www.thecanadianencyclopedia.com/