デヴィッド・トンプソン（David Thompson, 1770-1857）は、カナダ版の伊能忠敬（1745-1818）と言えばおそらくご理解いただけると思いますが、ヨーロッパ系のカナダ人やアメリカ人にとってほとんど人跡未踏と言えそうな土地を歩いて地図を作った人です（cartographer と言います）。19世紀前半のことです。だいたい現在のカナダの西側半分と、一部北緯49度線（アメリカとの国境線）を超えてその南のアメリカまで、およそ8万キロを徒歩やカヌーで移動して地図にしました。ちなみに、伊能が歩いた距離は、およそ4万キロと言われています。
Canadian Encyclopedia の記事から、冒頭部分をコピーします：
David Thompson, explorer, cartographer (born 30 April 1770 in London, England; died 10 February 1857 in Longueuil, Canada East). David Thomson was called “the greatest land geographer who ever lived.” He walked or paddled 80,000 km or more in his life, mapping most of western Canada, parts of the east and the northwestern United States. And like so many geniuses, his achievements were only recognized after his death.
もう少し知りたいという人のために、もう少しコピーしておきましょう：
Thompson learned astronomy and mathematics and spent so much time examining the sun and stars that he lost his sight in one eye. He broke his leg and it healed badly and he had a limp for the rest of his life. Yet this one-eyed, limping man mapped more territory than any other European. He surveyed the territory west of Lake Superior and the 49th parallel, which eventually became the dividing line between Canada and the United States. He mapped the north and paddled to the west coast. He mapped not only the land but also the cultural and religious practices of its inhabitants. His journals (which numbered hundreds of pages) and his maps provided the most complete record of a territory that was more than 3.9 million square km and contained dozens of different First Nations bands.
In 1799, Thompson married a Métis woman named Charlotte Small. He was 29; she was 13. It was a love affair that lasted 58 years. They had 13 children, 5 of them while he was still exploring. Thompson often took those children and his wife on his trips, venturing into unknown, sometimes hostile territory. At the Hudson’s Bay Company, he was valued as a fur trader, but Thompson wanted to explore rather than trade. He left the HBC and joined the rival North West Company where he spent the next 15 years exploring. In all, he spent 27 years mapping the west. “The age of guessing is passed away,” he wrote. Thompson predicted the changes that would come to the west, that it would become farmland and Indigenous peoples would be pushed from their land. As the one who mapped it, he was aware that he was contributing to that future.
伊能忠敬は50を過ぎてから測量の旅に出ました。トンプソンはもっと若くから地図作りを始めましたが、身体に不自由なところがあったりして、別の苦労があったでしょう。元々はハドソン湾会社（Hudson's Bay Company：以前の書き込み「2つのバンクーバー」で少し触れました。歴史で習った「東インド会社」みたいな「会社」です）の下で先住民相手の毛皮交易の仕事についていて、先住民の言葉もいくつか習得していました（のちにライバル会社であるノースウェスト会社に移籍）。彼はメイティ（Métis：ヨーロッパ系の人と先住民の間に生まれた人）の女性を妻にして、このことが彼の地図作りの旅に役立ったこともあったようです。
オンタリオ州公文書館のデータにある、トンプソンの足跡をたどった地図です（"Thompson's Travels," Archives of Ontario）。
このトンプソンの功績を特集したドキュメンタリーがあるので、興味のある方はご覧ください：
Uncharted Territory: David Thompson on the Columbia Plateau (KSPS Public TV)