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Spanish:

Guerra de 1847 or Guerra de Estados Unidos a Mexico ("War of the United States Against Mexico")

What was the Mexican-American War?

What did the Mexican-American War have to do with Manifest Destiny?

Was there opposition to the Mexican-American War within the United States?

What did the U.S. gain by winning the Mexican-American War?

How did the Mexican-American War increase sectionalism in the United States?

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Mexican-American War, war between the United States and Mexico (April 1846-February 1848) stemming from the United States' annexation of Texas in 1845 and from a dispute over whether Texas ended at the Nueces River (Mexican claim) or the Rio Grande (U.S. claim). The war-in which U.S. forces were consistently victorious-resulted in the United States' acquisition of more than 500,000 square miles (1,300,000 square km) of Mexican territory extending westward from the Rio Grande to the Pacific Ocean.

"American blood on American soil": Polk and the prelude to war

Mexico severed relations with the United States in March 1845, shortly after the U.S. annexation of Texas. In September U.S. Pres. James K. Polk sent John Slidell on a secret mission to Mexico City to negotiate the disputed Texas border, settle U.S. claims against Mexico, and purchase New Mexico and California for up to $30 million. Mexican Pres. José Joaquín Herrera, aware in advance of Slidell's intention of dismembering the country, refused to receive him. When Polk learned of the snub, he ordered troops under Gen. Zachary Taylor to occupy the disputed area between the Nueces and the Rio Grande (January 1846).

On May 9, 1846, Polk began to prepare a war message to Congress, justifying hostilities on the grounds of Mexican refusal to pay U.S. claims and refusal to negotiate with Slidell. That evening he received word that Mexican troops had crossed the Rio Grande on April 25 and attacked Taylor 's troops, killing or injuring 16 of them. In his quickly revised war message-delivered to Congress on May 11-Polk claimed that Mexico had "invaded our territory and shed American blood on American soil."

Spot Resolutions and Civil Disobedience: American opposition to the war

Congress overwhelmingly approved a declaration of war on May 13, but the United States entered the war divided. Democrats, especially those in the Southwest, strongly favoured the conflict. Most Whigs viewed Polk's motives as conscienceless land grabbing. Indeed, from the outset, Whigs in both the Senate and the House challenged the veracity of Polk's assertion that the initial conflict between U.S. and Mexican forces had taken place in U.S. territory. Further, legislators were at odds over whether Polk had the right to unilaterally declare that a state of war existed. Principally at issue was where the encounter had actually taken place and the willingness of Americans to acknowledge the Mexican contention that the Nueces River formed the border between the two countries. Active Whig opposition not only to the legitimacy of Polk's claim but also to the war itself continued well into the conflict. In December 1846 Polk accused his Whig doubters of treason. In January 1847 the by-then Whig-controlled House voted 85 to 81 to censure Polk for having "unnecessarily and unconstitutionally" initiated war with Mexico.

Among the most-aggressive challenges to the legitimacy of Polk's casus belli was that offered by future president Abraham Lincoln, then a first-term member of the House of Representatives from Illinois. In December 1847 Lincoln introduced eight " Spot Resolutions," which placed the analysis of Polk's claim in a carefully delineated historical context that sought to

obtain a full knowledge of all the facts which go to establish whether the particular spot of soil on which the blood of our citizens was so shed was, or was not, our own soil at that time.

Ultimately, the House did not act on Lincoln's resolutions, and Polk remained steadfast in his claim that the conflict was a just war.

Abolitionists saw the war as an attempt by the slave states to extend slavery and enhance their power with the creation of additional slave states out of the soon-to-be-acquired Mexican lands. One abolitionist who agreed with that interpretation was author Henry David Thoreau, who was incarcerated in July 1846 when he refused to pay six years' worth of back poll taxes because he felt the U.S. government's prosecution of the war with Mexico was immoral. Although he spent only a single night in jail (his aunt, against his wishes, paid the taxes, thus securing his release), Thoreau documented his opposition to the government's actions in his famous book-length essay Civil Disobedience (1849), insisting that if an injustice of government is

of such a nature that it requires you to be the agent of injustice to another, then, I say, break the law. Let your life be a counter friction to stop the machine.

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Mexican-American War | Significance, Battles, Results, Timeline, & Facts

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Mexican-American War, war between the U.S. and Mexico from 1846 to 1848. It was caused by a territorial dispute stemming from the United States' annexation of Texas in 1845 and from contention over whether Texas ended at the Nueces River or the Rio Grande.

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The Mexican-American War was fought between the United States  and Mexico. It lasted from1846 to 1848. It added hundredsof thousands of square miles tothe United States’ territory andaffirmed the American belief in manifest  Destiny.

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In 1845, Texas joined the United States as the 28th state. Mexico didn't like that the United States took over Texas. There also was a disagreement over the border of Texas. Mexico said the border was at the Nueces River while Texas claimed the border was further south at the Rio Grande River.

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The Mexican-American War was waged for two years on three fronts, and clashes between the American army and the Mexicans were frequent. There were about ten major battles: fights which involved thousands of men on each side. The Americans won all of them through a combination of superior leadership and better training and weapons.

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In 1846 the US went to war with Mexico over disputed territory on the Texas boarder.

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Picture

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Between 1846 and 1848, a war fought between two North American nations, the United States and Mexico, did what most wars do- it began with a bullet, it took lives, it ended with a treaty, and it made its mark on history's timeline. Yet, it often seems to be a mark whose boldness is not perceived.

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The key people involved were James k. Polk, Winfield scoot, Zachary Taylor, Stephan w. Kearny, John prance Sloat, William jeinkins w., Robert field  stocktak, and Joseph lane.

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April 25, 1846.
The Mexican-American War begins when Mexican troops cross north of the Rio Grande River and opened fire on U.S. troops at Fort , Texas. May 8, 1846.
Battle of Palo Alto- The first official battle of the war.

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General Winfield Scott's entrance into Mexico City, September 14, 1847, is depicted in this print by Carl Nebel

When war broke out against Mexico in May 1846, the United States Army numbered a mere 8,000, but soon 60,000 volunteers joined their ranks. The American Navy dominated the sea. The American government provided stable, capable leadership. The economy of the expanding United States far surpassed that of the fledgling Mexican state. Morale was on the American side. The war was a rout.

Polk directed the war from Washington, D.C. He sent a 4-prong attack into the Mexican heartland. John Fremont and Stephen Kearny were sent to control the coveted lands of California and New Mexico. Fremont led a group of zealous Californians to declare independence even before word of hostilities reached the West. The "Bear Flag Republic" was not taken seriously, but Fremont and his followers did march to Monterey to capture the Mexican presidio, or fort. By 1847, California was secure.

The original Treaty of Guadalupe Hidalgo was printed in two columns, the English translation on the left and the Spanish on the right.

Meanwhile, Kearny led his troops into Santa Fe in August of 1846 causing the governor of New Mexico to flee. The city was captured without a single casualty. Soon he marched his army westward across the desert to join Fremont in California.

The attack on Mexico proper was left to two other commanders. Zachary Taylor crossed the Rio Grande with his troops upon Polk's order. He fought Santa Anna's troops successfully on his advance toward the heart of Mexico. Winfield Scott delivered the knockout punch. After invading Mexico at Vera Cruz, Scott's troops marched to the capital, Mexico City. All that remained was negotiating the terms of peace.

At home, the Whigs of the north complained bitterly about the war. Many questioned Polk's methods as misleading and unconstitutional. Abolitionists rightly feared that southerners would try to use newly acquired lands to expand slavery. Antiwar sentiment emerged in New England much as it had in the War of 1812. Writer Henry David Thoreau was sentenced to prison for refusing to pay the taxes he knew were used to fund the war effort. His essay, Civil Disobedience, became a standard of peaceful resistance for future activists.

The Mexican-American War was formally concluded by the Treaty of Guadalupe-Hidalgo. 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. Although suffering 13,000 killed, the military won every engagement of the war. Mexico was stripped of half of its territory and was not consoled by the monetary settlement.

The U.S.-Mexican War, 1846-1848
An outstanding site for just browsing or for conducting serious research on the Mexican-American War. Images, documents, maps, timelines, statistics, and much more is brought to you by the Descendants of Mexican War Veterans. Easy-to-navigate and beautifully illustrated.

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The U.S.-Mexican War (1846-1848)
The Mexican-American war (1846-1848) changed the slavery debate. It almost doubled the size of the United States and began a debate, between Northerners and Southerners, over what to do with the newly acquired land.

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General Winfield Scott's entrance into Mexico City, September 14, 1847, is depicted in this print by Carl Nebel When war broke out against Mexico in May 1846, the United States Army numbered a mere 8,000, but soon 60,000 volunteers joined their ranks. The American Navy dominated the sea.

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Polk asks for war with Mexico. Northern Whigs fear victory would add more slave states to U.S. Declaration passes 40-2 in Senate, 174-14 in House. Whig Congressman Lincoln asks for the spot on American soil where American blood was shed.

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This was when the Americans were taking over a fort in Mexico.

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This picture marks the day the war started . And the war started in 1846 and ran thourgh 1848