William Gilpin (1815–1894) has been called “America’s first geopolitician.” Regarded today as both scientist and quack, Gilpin was in his own time a recognized authority whose maps were accepted by Congress as the most accurate available, and his description of trails and land in the West were read by pioneer and scientist alike as inspiration and guide. His writings first introduced to the American public the treasures of the Great Plains (to Gilpin probably belongs the credit for introducing this well-known term) and the mountain plateaus of the Rockies. He advertised the future of the lush valleys of Oregon and the mineral riches that, he was sure, the American West contained. Gilpin was a cultured, educated man; his studies and his hours of lonely observation on many trips across the American prairies had resulted in the theory—in part true, in part fallacious—about the importance of the Mississippi Valley to world trade and world peace. To his contemporaries and a few later historians he was “a man of rare genius and advanced thought, a prophet and pioneer of civilization,” “one of the wonderful and gifted men of the age, and to him are the citizens of the Republic, in general, and the West, in particular, immeasurably indebted.” In this biography Thomas L. Karnes traces the life of William Gilpin from the quiet comfort of his wealthy Quaker boyhood home through an exciting and turbulent career as Indian fighter, pioneer, newspaper editor, explorer, land promoter, and first governor of Colorado Territory. But throughout his varied career there was one task to which Gilpin was always devoted: he was a publicizer of the West, first in letters to family and friends; then in newspaper articles, books, and speeches; and finally in reports that became part of the Congressional Record and that influenced the actions of Presidents.