The Mexican-American War and the Treaty of Guadalupe Hidalgo
So far from God, so close to the United States – Old Mexican Saying
On September 14, 1847 the Mexican flag was not flying over the Mexican capital. Instead, Mexico’s neighbor to the north had captured the country. How and why did the United States defeat Mexico in the Mexican-American War? To the victors went what spoils? This essay will answer these questions in a nutshell.
Throughout the 19th Century, the United States was increasing in power and population while Mexico was stuck in chronic “political unrest, civil conflicts, depleted treasuries, [and] separatist movements” (Oscar J. Martinez, Troublesome Border [Tucson: the University of Arizona Press, 1988], 51). The U.S. was also heavily influenced by Manifest Destiny—the idea that the U.S. had the natural right to rule North America from coast to coast. Consequently, various presidential administrations in the 1820s and 30s sought to purchase land from Mexico, with no avail.
In 1835, Texas battled and gained independence from Mexico; Texas was a sovereign country for the next decade (the Lone Star Republic). In the Treaty of Velasco, the Texas-Mexico border was established along the Rio Grande. Mexican President Antonio Lopez de Santa Anna (pronounced “Santana”) signed the treaty but the problem lied in the fact that the Mexican Congress did not ratify it, nor did Mexican presidents after Santa Anna acknowledge Texas’ independence.
Texas was annexed by the United States in 1845. Mexico claimed the international border to be the Nuecos River, while the U.S. claimed the border to be at the Rio Grande. The Nuecos River runs roughly parallel to the Rio Grande about fifty to one-hundred miles northeast (the Texas side) of it. Therefore, by claiming their respective river boundaries, both countries were trying to expand their territory. When the Mexican army crossed the Rio Grande and skirmished with U.S. soldiers, President Polk declared that America had been invaded and American blood had been shed. These words meant one thing: war.