Clark's Map of 1810


When the United States purchased Louisiana from France in April 1803, the extent and character of the land was uncharted. On May 14, 1804, Captains Meriwether Lewis and William Clark set out on an expedition to explore the new territory that would fundamentally change Americans’ conceptions of their country. Clark served as the expedition’s principal cartographer. After completing the three-year journey from St. Louis to the Pacific Ocean and back, Clark worked at compiling a comprehensive map of the American West, using his personal knowledge and information gleaned from interviews with Native Americans and the accounts of army officers and fur traders. Shown here is the manuscript of his map, which he completed in 1810. Clark’s map served as a valuable guide for trappers, traders, scientists, and adventurers, as well as shaped, for more than a quarter century, how Americans understood the geography of the American West.

Last updated: October 19, 2015