When it appeared in 1949, the first edition of Ray Allen Billington's 'Westward Expansion' set a new standard for scholarship in western American history, and the book's reputation among historians, scholars, and students grew through four subsequent editions. This abridgment and revision of Billington and Martin Ridge's fifth edition, with a new introduction and additional scholarship by Ridge, as well as an updated bibliography, focuses on the Trans-Mississippi frontier. Although the text sets out the remarkable story of the American frontier, which became, almost from the beginning, an archetypal narrative of the new American nation's successful expansion, the authors do not forget the social, environmental, and human cost of national expansion.