The Mexican War Essay Research Paper IntroductionBeginning

The Mexican War Essay, Research Paper Introduction Beginning in 1845 and ending in 1850 a series of events took place that would come to be known as the Mexican war and the Texas Revolution. This paper will give an overview on not only the events that occurred (battles, treaties, negotiations, ect.) But also the politics and reasoning behind it all.

The Mexican War Essay, Research Paper


Beginning in 1845 and ending in 1850 a series of events took place that would come to be known as the Mexican war and the Texas Revolution. This paper will give an overview on not only the events that occurred (battles, treaties, negotiations, ect.) But also the politics and reasoning behind it all. This was a war that involved America and Mexico fighting over Texas. That was the base for the entire ordeal. This series of events contained some of the most dramatic war strategy that has ever been implemented.

What Caused This War?

In 1845 the U.S attempted to Annex Texas. Basically America wanted Texas to become one of the states rather then and independent nation by itself. At this time Texas was an independent nation that was not a part of America or Mexico. Mexico wanted to keep Texas neutral if not a part of its own country. When the U.S attempted to annex Texas Mexico became outraged, “ In November 1843 Mexico had warned that if the United States should commit the ‘unheard-of aggression’ of seizing an integral part of ‘Mexican territory’ Mexico would declare war ” (Bound for the Rio Grande, 62). Despite the warning the U.S attempted to annex Texas. In doing so Mexico retaliated by breaking off all diplomatic relations with the U.S. Mexico felt that the U.S was insulting them by not taking them seriously when they threatened with war. So at this point America showed a very large interest in possessing Texas. America was very close to actually acquiring Texas when they made their first mistake in the war.

The U.S requested the also be given the Rio Grande. The Rio Grande was south of Texas and clearly belonged to Mexico (refer to figure 1). The U.S felt that the Rio Grande was part of Texas and should be given to the U.S with Texas. Mexico would not give up the Rio Grande because they were certain that the Rio Grande belonged to them. America’s greed is THE major reason this conflict occurred. The U.S also believed the Mexico should have to pay for any of the U.S’s debts that were incurred during Mexico’s conflicts with Spain. America was in debt 3 million dollars because of the Mexico and Spanish conflicts and America very strongly believed that these debts were Mexico’s fault and they should have to pay for them. Mexico felt like it was Americas fault that they had to pay anything and they [Mexico] should not have to pay “ Mexico felt no obligation to pay and they felt as though America was attempting to use them as a source of income” (The Texas Military Experience, Website)

These are all legitimate reasons for this war to occur but they did not have the effect of “Manifest Destiny”. During this time in American history America had the growing feeling of Manifest Destiny. This was the desire to expand westward. This westward movement brought many Americans into Mexican territory. At this time Mexico controlled California and most of the southern portions of the western territories. Mexico’s problem was that even though they possessed these territories they did not have a population and large enough Military force to control them. They were unable to dictate or populate the territories so America basically took them over without a fight. Mexico was very frustrated with this predicament they were in, too much territory not enough men to control it.

Some Events Leading Up to the War

The tension was mounting between the U.S and Mexico. Some people could see war in the future but U.S President James K. Polk was in charge of this situation. He decided to use avoid taking these territories by force and try to buy them from Mexico.

President Polk sent John Slidell to buy New Mexico and California for 25 million dollars. In this deal the U.S would allow Mexico to keep the Rio Grande and the U.S would withdraw and troops from Mexican territories. The President of Mexico at this time was Santa Anna. Santa Anna was infuriated with the U.S at this point in time and he refused to see Slidell about negotiating the territories. So John Slidell returned to President Polk without ever having seen Santa Anna. So President Polk went with “Plan B” and started Mobilizing Troops. He ordered major Zachary Taylor to advance towards the Rio Grande. Major Taylor was given 4,000 men for his campaign. On April 25th, 1846 a party of Mexican Soldiers surprised and defeated a small group of Major Taylor’s cavalry just north of the Rio Grande. After this President Polk approached Congress with the suggestion of declaring war on Mexico, after Congress heard about the slaughter of the American cavalry they agreed with Polk. On May 13th, 1846 the U.S declared war on Mexico.

Great Leaders in the War

The first of many great leaders in this conflict would have to be President James Polk (see figure 2). He was president when the United States achieved its greatest territorial growth. During his presidency, the American flag was raised over most of the area now forming nine Western States, and Texas became a member of the Union. Polk successfully directed the Mexican War, which won much of this territory. He carried out every item of his political program “Of all other American presidents, only George Washington had such a clear record of success ” (world book Polk). After President Polk, would be General Zachary Taylor (see figure 3). His courage and leadership made him a national hero. General Taylor won many crucial battles in the beginning middle and end of this war. After the war he used his heroism as a base to become President. He became president but died after 16 months in office. General Scott was next on the political hierarchy. General Scott was one of the best strategists in the war. He was capable of winning as the under-dog at both Conteras and Churubusco. His walked his troops in to Mexico City after he captured it. His biggest victory was when he captured Vera Cruz.

Finally we meet the leader of the Mexican Army, President Santa Anna (see figure 4).

Santa Anna was the leader of the Mexican forces. He was elected 11 times but he was often overthrown due to his ruling as a dictator. But he was a great politician and did a good job at looking out for Mexico’s Best interests.

Battles in the War

One of the first battles fought was the battle of Palo Alto. General Taylor’s troops met the Mexican Forces commanded by Mariano Arista on a plain just northeast of Brownville, Texas. This took place on May 8th, 1846. The first large-scale battle was the Battle of Resaca de la Palma. This took place on May 9th, 1846, just a day after the battle of Palo Alto. General Taylor Taylor’s army of 2,300 men destroyed 5,000 men under Arista. Taylor’s first two victories allowed him to cross the Rio Grande and invade Mexico. Taylor continued his campaign with the battle of Buena Vista. Taylor’s 5,000 men defended a narrow mountain pass against Santa Anna’s Army containing around 18,000 men. After 48 hours of fighting Taylor’s troops stood victorious. With this Victory General Taylor established a firm hold on Northeastern Mexico. This battle was fought from February 22nd – February 24th, 1847 near the ranch of Buena Vista. Directly following these 3 battles was one of the most important battles of the entire way. This was the battle of Cerro Gordo. About a month after Buena Vista Both Santa Anna and General Taylor has reinforced their Armies in hopes of wiping the other out. On April 17th, 1846 General Taylor met Santa Anna on a narrow Mountain pass near Japala. General Taylor’s 9,000 men forced Santa Anna’s 13,000 men to flee after only a day of fighting. This battle cleared the way for Taylor’s men to invade Mexico City. After this battle General Taylor established himself as one of the premier generals in the U.S. General Taylor had showed consistently that he could win with an army much smaller then one of his opponents.

The American General Adam Scott fought the next large battle at Churubusco. General Scott’s soldiers stormed the fortified Mexican camp at Conteras. General Scott’s 9,000 men attacked the camp or 30,000 Mexican troops and won. The camp was in the small village of Churubusco 6 miles south of Mexico City. After about a day of fighting the American troops has pushed the Mexicans all the way back to the City where the Mexicans sought refuge within the walls of the capital city. Scott’s men followed into Chapultepec. Chapultepec was the last battle of the war before the capture of Mexico City. Scott’s men attacked Chapultepec which was a fortified hill guarding the city gates.

Scott’s men did not let up for an entire day until finally the Mexican soldiers went into the capital city. On September 12th Scott’s men began their attacks and on the 14th they entered Mexico City.

Probably one of the most legendary battles that has ever been fought was the Battle at the Texas mission known as the Alamo “The Alamo was the culmination of all the rage and hatred that had built up in the southwest during the 1830’s” ( Chapter 3, essay 1) In the battle at the Alamo Santa Anna’s forces attacked the mission for 13 days. The Texans had been using this mission as a fortification and the tried their best to defend it. After 12 days the Texans had run out of ammunition. With nothing but their fists and swords to fight with they held strong as the Mexicans stormed the Mission. The Texans fought with passion and courage but lost in the end because of their lack of ammunition. The Siege of the Alamo lasted from February 23rd – March 6th 1836.

Results Of the War

The war resulted in 13,000 American soldiers dead and over 71 million dollars in costs. The U.S gained over 525,000 square miles of land, the U.S Gained California, and other smaller portions of southwestern states. At this time the issue of slaves was a very heated one. It was decided by the U.S government that the new territory would be made slave free once it was inhabited. The war gave crucial training to many future soldiers who would fight and lead in the civil war. Some of these men include :

1. Ulysses S. Grant

2. William T. Sherman

3. George B. McClellan

4. George Gordon Meade

5. Robert E. Lee

6. Stonewall Jackson

All of these men also performed in some fashion in the Mexican war and Texas Revolution.

Despite all of Americas Victories Mexico refused to sign a peace treaty. Santa Anna then resigned and the new government agreed to sign the treaty. The treaty was signed February 2nd 1848 at the village called Guadalupe Hidalgo. In the agreement the U.S paid Mexico $15 million for the territories that became known as the Mexican secession.


The Mexican War was fought between the United States and Mexico over disagreements that had been accumulating for two decades. In the course of the war, United States forces invaded Mexico and occupied the capital, Mexico City. By the Treaty of Guadalupe Hidalgo, the United States acquired from Mexico the regions of California, Nevada, and Utah, most of Arizona and New Mexico, and parts of Colorado and Wyoming. But many historians believe the war was an unnecessary attack on a weaker nation. I believe that the war was unnecessary. I don’t think it needed to be fought at all and that over time the U.S could have acquired more of the western territory. This was a war fought because of greed not because of oppression or belligerence but on the grounds of greed alone. I do not think that the loss of that many men was necessary to accomplish the goal of gaining western territory.