"Less celebrated than his contemporaries Meriwether Lewis and William Clark, David Thompson spent nearly three decades, beginning in 1784, surveying and mapping more than 1.2 million square miles of largely uncharted Indian territory. Traveling across the prairies, over the Rockies, and on to the Pacific, Thompson transformed the raw data of his explorations into a map of the Canadian West. Measuring ten feet by seven feet and laid out with astonishing accuracy, the map became essential to the politicians and diplomats who would decide the future of the rich and promising lands of the West. Yet its creator worked without personal glory and died in penniless obscurity. Drawing extensively on Thompson's personal journals, illustrated with his detailed sketches, intricate notebook pages, and the map itself, "Epic Wanderer" charts the life of a man who risked everything in the name of scientific advancement and exploration."--Book jacket.