Land acquisition was essential to U.S. nation-building during the antebellum era due in part to the nineteenth century concept of Manifest Destiny. This was an ideology adopted by the United States that justified expansion through conquest and displacement of Indigenous nations. It was empowered by United States nativists, who also propagated anti-immigrant and xenophobic sentiment. The west, controlled by Mexico, indigenous tribes, and native people, was the ideal place for America to realize this dream.
Over the course of the 19th century, this land would see violent turnover: Americans settled in the area would fight to win independence from Mexico, Texas would be formed and later annexed to the United States, and President Polk would send troops to fight over disputed land. Eventually, the United States would easily take over half of insolvent Mexico’s territory in the U.S.-Mexican War (1845-49), namely acquiring land that would become the states of New Mexico and California. The Treaty of Guadalupe Hidalgo (1848) ended the war, detailed the requirements of Mexico’s land cessation, and inscribed a new political border. Starting with this treaty, the border would be constructed by both nations over the next century.
Although this was now legally American soil, the lines between native people and new American settlers was not clearly demarcated. These groups continued to coexist, meaning that the borderlands, now divided geographically and politically, was never separated culturally. The efforts for residents to live in the borderlands continues. In the words of revolutionary scholar Gloria E. Anzaldua: “At some point, on our way to a new consciousness, we will have to leave the opposite bank, the split between the two mortal combatants somehow healed so that we are on both shores at once and, at once, see through serpent and eagle eyes.”