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.
Postage stamps and postal history of Mexico
Mexico declared independence from Spain on September 16, 1810. This resulted in the long Mexican War of Independence which ended in 1821, and which eventually led to the creation of the short-lived First Mexican Empire. Agustín de Iturbide was the first and only emperor. Two years later, he was deposed by the republican forces. In 1824, a republican constitution was adopted, creating the United Mexican States with Guadalupe Victoria as its first President.