History of Hispanic and Latino Americans in the United States
In 1821, Mexico gained independence from Spain, annexing the southwest of the present United States, including Arizona. As missions began to wither, Mexico began auctioning off more land, causing the Pimería Alta and the Apachería to shrink as territory expanded. In the meantime, American mountain men began to enter the region, looking to trap beavers for their pelts. In 1836, Texas declared independence from Mexico and claimed much of the territory in the northern lands of Mexico. When the United States annexed Texas in 1846 over the strong objections of the Mexican government, U.S. troops moved into disputed territory. The hostilities erupted in the Mexican–American War (1846–1848). The U.S. occupied Mexico City and forced the newly founded Mexican Republic to give up its northern half, including the later Arizona.
New Mexico
New Mexico received its name long before the present-day nation of Mexico won independence from Spain and adopted that name in 1821. Spanish explorers recorded this region as New Mexico ("" in Spanish) in 1563. In 1581, the Chamuscado and Rodríguez Expedition named the region north of the Rio Grande "San Felipe del Nuevo México". The Spaniards hoped to find wealthy Mexican Indian cultures there similar to those of the Aztec (Mexica) Empire of the Valley of Mexico. The indigenous cultures of New Mexico, however, proved to be unrelated to the Aztecs, and were not wealthy. Before statehood, the name "New Mexico" was applied to various configurations of the U.S. territory, to a Mexican state, and to a province of New Spain, all in the same general area, but of varying extensions.