Causes of the Mexican-American War Texas gained its independence from Mexico in 1836. Initially, the United States declined to incorporate it into the union, largely because northern political interests were against the addition of a new slave state.
The Mexican-American War and the massive territory gained reopened debates over slavery which diminished party alliances and increased sectional alliances. These debates over slavery eventually led to the demise of the Second Party System and paved the way for the rise of Republicanism.
It pitted a politically divided and militarily unprepared Mexico against the expansionist-minded administration of U.S. President James K. Polk, who believed the United States had a “manifest destiny” to spread across the continent to the Pacific Ocean.
Mexican-American War: U.S. Army Advances Into Mexico At that time, only about 75,000 Mexican citizens lived north of the Rio Grande. As a result, U.S. forces led by Col. Stephen W. Kearny and Commodore Robert F. Stockton were able to conquer those lands with minimal resistance.
The vast majority were victims of diseases such as dysentery, yellow fever, malaria and smallpox. According to scholar V.J. Cirillo, a higher percentage of U.S. troops died from sickness during the Mexican invasion than any war in American history.
The treaty added an additional 525,000 square miles to United States territory, including the land that makes up all or parts of present-day Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming. Mexico also gave up all claims to Texas and recognized the Rio Grande as America's southern boundary.
The United States received the disputed Texan territory, as well as New Mexico territory and California. The Mexican government was paid $15 million — the same sum issued to France for the Louisiana Territory. The United States Army won a grand victory.
Mexico ceded nearly all the territory now included in the U.S. states of New Mexico, Utah, Nevada, Arizona, California, Texas, and western Colorado for $15 million and U.S. assumption of its citizens' claims against Mexico.
The Mexican-American War Begins. On April 25, 1846 , Mexican cavalry attacked a group of U.S. soldiers in the disputed zone under the command of General Zachary Taylor, killing about a dozen. They then laid siege to an American fort along the Rio Grande.
Treaty of Guadalupe Hidalgo Ends the Mexican-American War. The Mexican-American War (1846-1848) marked the first U.S. armed conflict chiefly fought on foreign soil. It pitted a politically divided and militarily unprepared Mexico against the expansionist-minded administration of U.S. President James K.
Under the treaty, Mexico also recognized the U.S. annexation of Texas, and agreed to sell California and the rest of its territory north of the Rio Grande for $15 million plus the assumption of certain damages claims.
A border skirmish along the Rio Grande started off the fighting and was followed by a series of U.S. victories. When the dust cleared, Mexico had lost about one-third of its territory, including nearly all of present-day California, Utah, Nevada, Arizona and New Mexico.
Initially, the United States declined to incorporate it into the union, largely because northern political interests were against the addition of a new slave state. The Mexican government was also encouraging border raids and warning that any attempt at annexation would lead to war.
They then began marching toward Mexico City , essentially following the same route that Hernán Cortés followed when he invaded the Aztec empire. The Mexicans resisted at Cerro Gordo and elsewhere, but were bested each time. In September 1847, Scott successfully laid siege to Mexico City ’s Chapultepec Castle.
Nonetheless, annexation procedures were quickly initiated after the 1844 election of Polk, who campaigned that Texas should be “re-annexed” and that the Oregon Territory should be “re-occupied.”. Polk also had his eyes on California, New Mexico and the rest of what is today the U.S. Southwest.
On February 2, 1848, the Treaty of Guadalupe Hidalgo was signed which officially ended the Mexican-American War. However, as the guns fell silent, and the men returned home, a new war was brewing, one that continues to shape the course of this country to this day.
With the Treaty of Guadalupe Hidalgo, Mexico ceded over 525,000 square miles of territory to the United States in exchange for $15 million and the assumption of Mexican debts to American citizens, which reopened the slavery issue. In order to promote party loyalty without aggravating sectional tensions, the Whigs did not include specific ...
In this time of heightened sectional tensions, southerners believed that if one did not actively protect slavery and its expansion, one supported abolition.
While controversial, the Compromise of 1850 alleviated the growing tensions over slavery and delayed a full-blown crisis over the issue.
Consequently, the Whigs and the Democrats developed campaign materials to be sectionally distributed which highlighted their candidate's support and opposition for slavery respectively.
As a direct result of the Mexican Cession, the California Gold Rush began in 1849 which caused a massive frenzy to organize and admit California into the Union. The Missouri Compromise stated that any territory north of the 36°30’ parallel would be free; however, the line would divide California into two sections.
The Democrats ran on popular sovereignty, which is the idea that the status of a territory will be determined by the people residing in that territory. Popular sovereignty is neither explicitly pro-slavery or anti-slavery; however, it does nullify the Missouri Compromise.