<P> When the Mexican--American War ended in 1848, Mexico ceded its northern zone to the United States and residents of that region became U.S. citizens . The Phoenix area became part of the New Mexico Territory . In 1863 the mining town of Wickenburg was the first to be established in what is now Maricopa County, to the northwest of modern Phoenix . At the time Maricopa County had not yet been incorporated: the land was within Yavapai County, which included the major town of Prescott to the north of Wickenburg . </P> <P> The U.S. Army created Fort McDowell on the Verde River in 1865 to forestall Native American uprisings . The fort established a camp on the south side of the Salt River by 1866, which was the first non-native settlement in the valley after the decline of the Hohokam . In later years, other nearby settlements would form and merge to become the city of Tempe, but this community was incorporated after Phoenix . </P> <P> The history of the city of Phoenix begins with Jack Swilling, a Confederate veteran of the Civil War . In 1867, while traveling through the Salt River Valley, he saw a potential for farming, much like the military had already cultivated further east, near Fort McDowell . He formed a small community that same year about four miles (six km) east of the present city . Lord Darrell Duppa, one of the original settlers in Swilling's party, suggested the name "Phoenix", as it described a city born from the ruins of a former civilization . </P> <P> The Board of Supervisors in Yavapai County, which at the time encompassed Phoenix, officially recognized the new town on May 4, 1868, and the first post office was established the following month, with Swilling as the postmaster . On February 12, 1871, the territorial legislature created Maricopa County, the sixth one formed in the Arizona Territory, by dividing Yavapai County . The first election for county office was held in 1871, when Tom Barnum was elected the first sheriff, running unopposed when the other two candidates, John A. Chenowth and Jim Favorite, fought a duel wherein Chenowth killed Favorite, and then was forced to withdraw from the race . </P>

Where did the city of phoenix get its name
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