The Dog Soldiers or Dog Men (Cheyenne: Hotamétaneo'o) are historically one of six Cheyenne military societies. Beginning in the late 1830s, this society evolved into a separate, militaristic band that played a dominant role in Cheyenne resistance to the westward expansion of the United States in the area of present-day Kansas, Nebraska, Colorado, and Wyoming, where the Cheyenne had settled in the early nineteenth century.