The Great Basin comprises the large interior depression lying between the Sierra Nevada to the west and the Rocky Mountains to the east. 
The natural Great Basin is a large region that includes most of Nevada, S.E. Oregon, S. Idaho, W. Utah, and a Portion of E California.  Within this region are two major deserts:  a) Mojave Desert (south); and b) Great Basin Desert (north).  The environment of the Great Basin is highly varied and includes alpine zones, forests, rivers, marshes, and very arid regions.
The first European contact with Great Basin native groups occurred in the Southwest in the early 17th century, when Utes and Southern Paiutes from the Basin began to raid the Spanish and Pueblo groups.