In the 1920s, the Denver Public Library created a Western history collection, recognizing that no other regional institution was better situated to preserve the history of Colorado and the Rocky Mountain West. By the mid-1930s, the Library moved to establish a department devoted to Western history, which opened in January 1935. The Department now collects for a region that includes all states of the Trans-Mississippi West, with a particular emphasis on Denver and the Rocky Mountain West. Our collections represent not only the nineteenth-century West, but also the twentieth- and twenty-first century Wests, with particular strengths in the history of mining, conservation, railroads, photography, and architecture and building history, as well as the history of Denver and Colorado. Our materials include a vast body of photographic and other images, with a substantial portion accessible online in digital form; a large, varied, and rapidly growing manuscript collection; a comprehensive map and atlas collection; a remarkable range of ephemera, including posters, broadsides, and pamphlets and other promotional materials; prints, paintings, sculpture, and other original Western art; and an extensive library of print materials, including books, periodicals, and newspapers. Unique to the Department is our Western History Subject Index, a name-and-subject index to The Rocky Mountain News (1865-1995), The Denver Post (1895-1980), and other Denver newspapers, supplemented with references to other materials. With millions of entries, the Subject Index directs users to a wealth of otherwise inaccessible information. Research Guide