Before the discovery of the sites for the Europeans the region known today as the state of Wyoming, a population of several groups of Indians, such as the Crow, Arapaho, Lakota and Shoshone. French trappers roamed the northern part of the state at the end of the eighteenth century, however, until in 1807 it was described by John Colter, a member of the Lewis and Clark expedition. His description of the cure panic attacks Yellowstone area was considered to be factual.