On October 31, 1864, Abraham Lincoln admitted Nevada to the Union to aid in the Civil War. American Indians may have lived in the Nevada region more than 20,000 years ago, making this area home to some of the earliest Indians in the United States. In southern Nevada, Indians left picture writing on rocks that date back thousands of years. Nevada tribes include the Pueblo, Mohave, Paiute, Shoshone, and Washoe. Historians believe Francisco Garcés was the first white man to reach Nevada. In 1776, Garcés went through the region while traveling from New Mexico to California. Between 1825 and 1830, many fur trappers came to Nevada. William Wolfskill blazed the Old Spanish Trail from Santa Fe to Los Angeles. This route made it possible for people in Nevada to trade with the southeast.