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.
Military history of Mexico
The military history of Mexico consists of several millennia of armed conflicts within what is now that nation's territory and includes activities of the Mexican military in peacekeeping and combat related affairs worldwide. Wars between prehispanic peoples marked the beginning of Mexico's military history, the most notable of these fought in the form of a "flower war". After the Spanish conquest of Mexico in the 16th century, indigenous tribes were defeated by Spain, thus beginning a three century era of Spanish dominance. Mexico's struggle for independence began primarily in the 19th century, and was marked by internal conflict of early rulers after defeating the Spanish in 1821. The Mexican–American War in the mid 19th century ended in the defeat of Mexican forces, and the loss of two-fifths of the national territory. In the remainder of the 19th century, a series of conflicts began in Mexico, as the War of the Reform and the defeat of the French during their intervention in Mexico marked events in that era.