William Clark, co-captain of the famous Lewis and Clark Expedition, devoted his adult life to describing the American West. But this task raised a daunting challenge: how best to bring an unknown continent to life for the young republic? Through Clark's life and career, this book explores how the West entered the American imagination. While he never called himself a writer or an artist, Clark nonetheless drew maps, produced books, drafted reports, surveyed landscapes, and wrote journals that made sense of the West for a new nation fascinated by the region's potential but also fearful of its dangers. William Clark's World presents a new take on the manifest destiny narrative and on the way the West took shape in the national imagination in the early nineteenth century.