The Mexican-American War of 1846 to 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. Polk, who believed the United States had a “Manifest Destiny” to spread across the continent to the Pacific Ocean. A border skirmish along the Rio Grande that started off the fighting 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.
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 state that supported slavery. The Mexican government was also encouraging border raids and warning that any attempt at annexation would lead to war.
Nonetheless, annexation procedures were quickly initiated after the 1844 election of Polk, a firm believer in the doctrine of Manifest Destiny, 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 American Southwest.
When his offer to purchase those lands was rejected, he instigated a fight by moving troops into a disputed zone between the Rio Grande and Nueces River that both countries had previously recognized as part of the Mexican state of Coahuila.
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 Fort Texas along the Rio Grande. Taylor called in reinforcements, and—with the help of superior rifles and artillery—was able to defeat the Mexicans at the Battle of Palo Alto and the Battle of Resaca de la Palma.
Following those battles, Polk told the U.S. Congress that the “cup of forbearance has been exhausted, even before Mexico passed the boundary of the United States, invaded our territory, and shed American blood upon American soil.” Two days later, on May 13, Congress declared war, despite opposition from some northern lawmakers. No official declaration of war ever came from Mexico.
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 Watts Kearny and Commodore Robert Field Stockton were able to conquer those lands with minimal resistance. Taylor likewise had little trouble advancing, and he captured the city of Monterrey in September.
With the losses adding up, Mexico turned to old standby General Antonio López de Santa Anna, the charismatic strongman who had been living in exile in Cuba. Santa Anna convinced Polk that, if allowed to return to Mexico, he would end the war on terms favorable to the United States.
But when Santa Anna arrived, he immediately double-crossed Polk by taking control of the Mexican army and leading it into battle. At the Battle of Buena Vista in February 1847, Santa Anna suffered heavy casualties and was forced to withdraw. Despite the loss, he assumed the Mexican presidency the following month.
Meanwhile, U.S. troops led by Gen. Winfield Scott landed in Veracruz and took over the city. 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 the Battle of Cerro Gordo and elsewhere, but were bested each time. In September 1847, Scott successfully laid siege to Mexico City’s Chapultepec Castle. During that clash, a group of military school cadets–the so-called niños héroes–purportedly committed suicide rather than surrender.
Treaty of Guadalupe Hidalgo
Guerrilla attacks against U.S. supply lines continued, but for all intents and purposes the war had ended. Santa Anna resigned, and the United States waited for a new government capable of negotiations to form.
Finally, on Feb. 2, 1848, the Treaty of Guadalupe Hidalgo was signed, establishing the Rio Grande (and not the Nueces River) as the U.S.-Mexican border. 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 damage claims.
The net gain in U.S. territory after the Mexican-American War was roughly 525,000 square miles, an enormous tract of land—nearly as much as the Louisiana Purchase’s 827,000 square miles—that would forever change the geography, culture and economy of the United States.
Though the war with Mexico was over, the battle over the newly acquired territories—and whether or not slavery would be allowed in those territories—was just beginning. Many of the U.S. officers and soldiers in the Mexican-American War would in just a few years find themselves once again taking up arms, but this time against their own countrymen in the Civil War.
Vita vya Mexico na Marekani vya 1846-1848 vilikuwa vita vya kwanza vya kijeshi vya Marekani kupigana katika nchi za kigeni. "Mexico ilikuwa imegawanyika kisiasa na haikuwa tayari kijeshi dhidi ya utawala wa Rais wa Marekani James K. Polk, ambaye aliamini kuwa Marekani ilikuwa na ""ajali ya wazi"" ya kuenea katika bara hadi Bahari ya Pasifiki." Mapigano ya mpaka kwenye mto Rio Grande yalianza na Marekani kushinda vita kadhaa. Wakati huo, Mexico ilikuwa imepoteza theluthi moja ya eneo lake, ikiwa ni pamoja na karibu California, Utah, Nevada, Arizona na New Mexico. Vita vya Mexico na Marekani: Texas ilipata uhuru kutoka Mexico mwaka 1836 Mwanzoni, Marekani ilikataa kuijumuisha katika muungano huo, hasa kwa sababu maslahi ya kisiasa ya kaskazini yalikuwa dhidi ya kuongezwa kwa jimbo jipya ambalo liliunga mkono utumwa. Serikali ya Mexico pia ilikuwa ikiwatia moyo watu wavamie mipaka na kuonya kwamba jaribio lolote la kuunganisha nchi hiyo lingesababisha vita. Hata hivyo, taratibu za kuunganisha zilianzishwa haraka baada ya uchaguzi wa 1844 wa Polk, mwamini thabiti katika mafundisho ya Manifest Destiny, ambaye alifanya kampeni kwamba Texas inapaswa "kuunganishwa tena" na kwamba Eneo la Oregon linapaswa "kuchukuliwa tena". Wakati ofa yake ya kununua ardhi hiyo ilipokataa, alianzisha mapigano kwa kuhamisha majeshi katika eneo lenye utata kati ya Mto Rio Grande na Nueces ambalo nchi zote mbili zilikuwa zimetambua hapo awali kama sehemu ya jimbo la Mexico la Coahuila. Vita vya Mexico na Marekani: Aprili 25, 1846 - Jeshi la wapanda farasi la Mexico lilishambulia jeshi la Marekani lililokuwa katika eneo lililokuwa na mgogoro chini ya uongozi wa Jenerali Zachary Taylor, na kuua askari kumi na wawili. Kisha wakazingira Ngome ya Texas kando ya Mto Rio Grande. Taylor aliita vikosi vya kuimarisha, na - kwa msaada wa bunduki na makombora bora - aliweza kuwashinda Wamexico katika Vita vya Palo Alto na Vita vya Resaca de la Palma. "Kama ilivyoelezwa katika makala ya kwanza ya makala ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya pili ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya tatu ya nne ya nne ya nne ya nne ya nne ya nne ya nne ya nne ya nne ya nne.""" Hakuna tangazo rasmi la vita lililowahi kutolewa na Mexico. Wakati huo, kulikuwa na raia wa Mexico 75,000 tu waliokaa kaskazini mwa Mto Rio Grande. Kwa sababu hiyo, majeshi ya Marekani yaliyoongozwa na Kanali Stephen Watts Kearny na Commodore Robert Field Stockton yaliweza kushinda nchi hizo bila upinzani mkubwa. Vivyo hivyo, Taylor hakuwa na tatizo la kusonga mbele, naye akachukua jiji la Monterrey mnamo Septemba. Baada ya kushindwa, Mexico ilimgeukia Jenerali Antonio López de Santa Anna, aliyekuwa akiishi uhamishoni nchini Cuba. Santa Anna alimshawishi Polk kwamba, ikiwa angeruhusiwa kurudi Mexico, angemaliza vita kwa masharti mazuri kwa Marekani. Santa Anna alipofika, Polk alishindwa na jeshi la Mexico. Katika vita vya Buena Vista, Santa Anna alishindwa na askari wake na kukimbia. Licha ya kushindwa, alichukua urais wa Mexico mwezi uliofuata. Wakati huohuo, majeshi ya Marekani yaliyoongozwa na Jenerali Winfield Scott yaliwasili Veracruz na kuuteka mji huo. Kisha wakaanza kusonga kuelekea Mexico City, wakifuata njia ileile ambayo Hernán Cortés alifuata alipovamia milki ya Waazteki. Wamexico walipinga katika Vita vya Cerro Gordo na kwingineko, lakini walishindwa kila mara. Mnamo Septemba 1847, Scott alifanikiwa kuzingira Ngome ya Chapultepec ya Mexico City. Wakati wa mapigano hayo, kikundi cha wanafunzi wa shule ya kijeshi - wanaoitwa niños héroes - walijaribu kujiua badala ya kujisalimisha. Mkataba wa Guadalupe Hidalgo ulifanya vita vya kupigana na wapiganaji wa kupigana dhidi ya Marekani, na kwa hivyo vita vilianza. Santa Anna alijiuzulu, na Marekani ilingoja serikali mpya yenye uwezo wa kujadiliana ifanywe. Mkataba wa Guadalupe Hidalgo ulifungwa tarehe 2 Februari 1848 na kuanzisha mpaka wa Mexico na Marekani. Mkataba huo ulionyesha Mexico ilikubali kuunganisha Texas na California na eneo lake la kaskazini mwa Rio Grande kwa dola milioni 15 na malipo ya uharibifu. Baada ya vita vya Mexico na Marekani, eneo la Marekani liliongezeka kwa kilomita 525,000 za mraba, karibu na eneo la Louisiana Purchase, ambalo lilibadilisha kwa milele jiografia, utamaduni na uchumi wa Marekani. Ingawa vita na Mexico vilikuwa vimekwisha, vita juu ya maeneo mapya yaliyopatikana - na kama utumwa ungeruhusiwa au la - zilikuwa zinaanza tu. Maofisa na askari wengi wa Marekani katika Vita vya Mexico na Marekani walianza tena kupigana, lakini wakati huu dhidi ya wananchi wao wenyewe katika Vita vya wenyewe kwa wenyewe.