David Thompson was born in England in 1770 and came to Canada to join the Hudson's Bay Company at the age of 14. He studied surveying with the Company and was soon carrying on important exploratory work in the Northwest. By the time he was 17, he had penetrated Western Canada as far as the site of present-day Calgary. David Thompson had an unusual ability to get along with the Indians, and his friendship with the various western tribes played an important part in the success of his work. Transferring to the North West Company in 1798, he devoted all his time to mapping and exploration. Before his death in 1857, he became famous for his achievements in the territories now forming the provinces of Alberta and British Columbia. An illustration of the explorer David Thompson holding a sextant. The map indicates the location of his greatest exploration.