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.
First Mexican Empire
After signing the Declaration of Independence of the Mexican Empire of 28 September 1821, the Mexican Congress intended to establish a commonwealth whereby the King of Spain, Ferdinand VII, would also be emperor of Mexico, and both countries would be governed by separate laws and form separate legislative bodies. If the king refused the position, the law provided for another member of the House of Bourbon to accede to the Mexican throne. However, the goal was merely a political tactic to appease the last royalists, and full independence was expected. King Ferdinand, however, refused to recognize Mexico's independence and said that Spain would not allow any other European prince to take the throne of Mexico.