The Wickenburg area with much of the Southwest became part of the United States by the 1848 treaty that ended the Mexican-American War. The first extensive survey was conducted by Gila Rangers who were pursuing hostile Indians who had raided the Butterfield Overland Mail route and attacked miners at Gila City.
In 1862, a gold strike on the Colorado River near present-day Yuma brought American prospectors, who searched for minerals throughout central Arizona. Many of the geographic landmarks now bear the names of these pioneers, including the Weaver Mountains, named after mountain man Pauline Weaver, and Peeples Valley, named after a settler.
A German named Henry Wickenburg was one of the first prospectors. His efforts were rewarded with the discovery of the Vulture Mine, from which more than $30 million worth of gold has been dug.