Linguistic and archaeological evidence argue for an arrival of Southern Numic-speakers in the eastern Great Basin and Plateau country about A.D. 1250-1350. At the time of European settlement in New Mexico in the 1600s and Utah in the late 1700s, the Ute were well established, but had developed along somewhat different trajectories. The Eastern Ute had converted to the horse-riding Plains life-style, and the Western Ute retained more traditional Great Basin patterns until the early 1800s when certain central Utah groups also adopted the horse and other Plains cultural trappings. Ute neighbors to the north, west, and east included other Numic-speakers, such as the Northern Shoshone, Western Shoshone, and Southern Paiute. Also to the south were the Pueblos, Navajo, and Apache. To the east were the Plains groups, such as the Wind River Shoshone (Numic-speakers), Arapaho, Comanche (Numic-speakers), and Southern Cheyenne. Relations were amicable with the Western Shoshone, but raids were common between the Ute and other Neighbors, especially the Plains peoples, with the exception of the Comanche. The unmounted Southern Paiute to the south were routinely subjected to raids by all Utes to obtain slaves, especially women and children, to trade to the Spanish.
Mormon immigration to the Great Basin in 1847 marked the beginning of the end for the traditional Western Ute way of life. Serious conflicts began in 1849, when settlers moved into Utah Valley, an important center of Ute settlement. Following the Walker War of 1850s and the Black Hawk War in the 1860s, all Western Ute were displaced from the eastern Great Basin and relocated in the Uinta Basin of northern Utah. For the Eastern Ute the process was slower. Reduction of lands began in the 1850s owing to a series of treaty agreements and continued until the 1880s. The Meeker Massacre of 1879 resulted in most of the northern Colorado Utes being placed on the Uinta Basin reservation. Other Eastern Utes moved to the small Southern Ute and Elk Mountain reservations in southwestern Colorado and northwestern New Mexico.