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
Yucatán had considered itself an independent nation, but during the crisis of the revolt had offered sovereignty to any nation that would aid in defeating the Indians. The Mexican government was in a rare position of being cash rich from payment by the United States under the Treaty of Guadalupe Hidalgo for the territory taken in the Mexican–American War, and accepted Yucatán's offer. Yucatán was officially reunited with Mexico on 17 August 1848. European Yucateco forces rallied, aided by fresh guns, money, and troops from Mexico, and pushed back the Maya from more than half of the state.