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.
Centralist Republic of Mexico
Months later, Antonio López de Santa Anna, in response to the declaration of independence, threatened to send in the troops if it was not reversed while also assuring the Tabasco authorities that Federalism would soon be reinstated. This combined threat and promise culminated in the reinstatement of Tabasco into the Mexican Republic on December 2, 1842. But four years later, Tabasco again declared its independence in November 1846 as a protest to the lack of Central government assistance in resisting the American occupation of its coast earlier that same year.