Mexican–American War

Mexican War
File:Battleveracruz.jpg The Battle of Veracruz
Date 1846–1848 Location Texas, New Mexico, California; Northern, Central and Eastern Mexico; Mexico City Result United States victory; Treaty of Guadalupe Hidalgo, Mexican Cession
Belligerents
United States	Mexico
Commanders and leaders
Zachary Taylor Winfield Scott Stephen W. Kearney	Antonio López de Santa Anna Mariano Arista Pedro de Ampudia José Mariá Flores
Strength
78,790 soldiers	18,000–40,000 soldiers
Casualties and losses
KIA: 1733 Total dead: 13,271 Wounded: 4,152 AWOL: 9,200+	25,000 killed or wounded (Mexican government estimate)

The Mexican War was a military conflict fought between the United States and Mexico from 1846 to 1848 in the wake of the 1845 U.S. annexation of Texas. Mexico did not recognize the secession of Texas in 1836; it considered Texas a rebel province.

In the United States, the war was a partisan issue with most Whigs opposing it and most Democrats, animated by a popular belief in the Manifest Destiny, supporting it. In Mexico, the war was considered a matter of national pride.

The most important consequence of the war was the Mexican Cession, in which the Mexican territories of Alta California and Santa Fé de Nuevo México were ceded to the United States under the terms of the Treaty of Guadalupe Hidalgo. In Mexico, the enormous loss (52 percent) of territory encouraged the central government to enact policies to colonize its northern territories as a hedge against further losses.

Background

After Mexico gained independence from the Spanish Empire at the end of its War of Independence in 1821, the Mexican Empire inherited the provinces of Alta California, Nuevo México, and Texas, from Spain. Weakened and virtually bankrupt from its War of Independence, the new government found it difficult to govern its northern territories, which in any case were thousands of miles from Mexico City, the capital.

Although the United States made overtures to the Mexican government to buy Texas, Mexico, ruled by the short-lived régime of Emperor Agustín Iturbide and his successor, Antonio López de Santa Anna, opposed selling Texas. Mexico intended to colonize its northern provinces.

Mexico's Constitution of 1835 prohibited slavery. Many Texans were slave owners who had emigrated from Tennessee and other slave states in the United States. These Texans objected to the abolition of slavery. They were further incensed in 1836 when General Santa Anna abolished the 1824 constitution and established a new constitution that attempted to centralize power. The new centralist constitution enshrined the Siete Leyes, which included secular reforms but granted additional powers to the president, such as the power to close Congress and suppress the judiciary. Several states rebelled against the new central government under Santa Anna, including Texas (then a department of the state of Coahuila y Tejas), San Luis Potosí, Querétaro, Durango, Guanajuato, Michoacán, Yucatán, Jalisco and Zacatecas.

A rebellion known as the Texas Revolution erupted in 1836. General Santa Anna responded by engaging in two battles against rebel forces, the Álamo and Goliad, and executing the rebels captured in these battles. This encouraged a wider revolt in Texas.

Republic of Texas

The Republic of Texas.The present-day outlines of the U.S. states are superimposed on the boundaries of 1836–1845.

In the 1836 Texas Revolution, Texas won its independence after defeating Santa Anna and the Mexican army. General Santa Anna was taken captive by the Texas militia and released after signing the Treaties of Velasco in which he promised to recognize the sovereignty of the Republic of Texas and the Rio Grande as the boundary between Texas and Mexico. The Mexican government, however, refused to acknowldge these concessions, arguing that Santa Anna was not a representative of Mexico, that he had no authority to negotiate on behalf of Mexico, and that he signed away Texas under duress. The Mexican government never ratifed the Treaties of Velasco.

In the decade after 1836, Texas consolidated its position as an independent republic by establishing diplomatic ties with Britain, France, and the United States. Most Texans were in favor of annexation by the United States, but U.S. President Andrew Jackson rejected it.

Under U.S. President John Tyler, Texas was offered admission to the Union as a territory. The bill was signed into law onMarch 1, 1845. It was ratified by Texas on July 4. Texas became the 28th state on December 28, a law signed by President James K. Polk.

The Mexican government had long warned that annexation would mean war with the United States. Britain and France, which recognized the independence of Texas, repeatedly tried to dissuade Mexico from declaring war. British efforts to mediate were fruitless in part because additional political disputes (particularly the Oregon boundary dispute) arose between Mexico, Britain, and the United States.

In 1845 President Polk sent diplomat John Slidell to Mexico City in an attempt to purchase Mexico's Alta California and Santa Fé de Nuevo México territories. U.S. expansionists wanted California to thwart British ambitions in the area and to have a Pacific Ocean port. Polk authorized Slidell to forgive the $4.5 million owed to U.S. citizens for damages caused by the Mexican War of Independence and pay another $25 to $30 million in exchange for the two territories.

However, Mexico was not inclined nor in a position to negotiate. In 1846 alone, the presidency changed hands four times, the war ministry six times, and the finance ministry sixteen times. In Mexico, public opinion and all political factions agreed that selling the territories to the United States would tarnish the national honor. Mexicans who opposed open conflict with the United States, including President José Joaquín de Herrera, were viewed as traitors. When de Herrera considered receiving Slidell in order to peacefully negotiate the problem of Texas annexation, he was accused of treason and deposed.

Military opponents of President José Joaquín de Herrera, supported by populous newspapers, considered Slidell's presence in Mexico City an insult. After a more nationalistic government under General Mariano Paredes y Arrillaga came to power, the new government publicly reaffirmed Mexico's claim to Texas; Slidell, convinced that Mexico should be "chastised," returned to the United States.[2]

Opening hostilities

Mexico claimed the Nueces River — about 150 miles (240 km) north of the Rio Grande — as its border with Texas; the United States upheld the Rio Grande as the boundary, as established by the 1836 Treaty of Velasco. Mexico, however, never ratified this treaty.

In 1846, after Texas was admitted into the Union, Polk sent militia under General Zachary Taylor to the Rio Grande to protect Texas. Taylor ignored Mexican demands to withdraw to the Nueces. He constructed a make-shift fort (later known as Fort Brown) on the banks of the Rio Grande opposite the Mexican town of Matamoros. Mexican forces under General Mariano Arista prepared for war.

On April 24, 1846, a 2,000-strong Mexican cavalry detachment attacked a 63-man U.S. patrol that was sent into the contested territory north of the Rio Grande and south of the Nueces River. The Mexican cavalry succeeded in routing the patrol, killing 11 U.S. soldiers in what later became known as the Thornton Affair after the slain U.S. officer who was in command. A few survivors returned to Fort Brown.

On May 3, Mexican artillery at Matamoros opened fire on Fort Brown, which replied with its own guns. The bombardment continued for five days and expanded as Mexican forces gradually surrounded the fort. Two U.S. soldiers were killed during the bombardment, including Jacob Brown, after whom the fort was later named.

On May 8, Zachary Taylor arrived with 2,400 troops to relieve the fort. However, Arista rushed north and intercepted him with a force of 3,400 at Palo Alto. The Americans employed "flying artillery," the American term for horse artillery, a type of mobile light artillery that was mounted on horse carriages with the entire crew riding horses into battle. U.S. artillery had a devastating effect on the Mexican Army. The Mexicans responded with cavalry skirmishes and its own artillery. The U.S. flying artillery somewhat demoralized the Mexican side, and seeking terrain more to their advantage, the Mexicans retreated to the far side of a dry riverbed (resaca) during the night. It provided a natural fortification, but during the retreat, Mexican troops were scattered, making communication difficult. During the Battle of Resaca de la Palma the next day, the two sides engaged in vicious hand to hand combat. The U.S. cavalry managed to capture the Mexican artillery, causing the Mexican side to retreat — a retreat that turned into a rout. Fighing on difficult terrain, his troops scattered, Arista found it impossible to rally his forces. Mexican casualties were heavy, and the Mexicans were forced to abandon their artillery and baggage. Fort Brown inflicted further casualties as the withdrawing troops passed by the fort. Many soldiers drowned trying to swim across the Rio Grande.

Declaration of war

By then, Polk had received word of the Thornton Affair. This, added to the Mexican government's rejection of Slidell, Polk believed, constituted a casus belli. His message to Congress on May 11, 1846 stated that Mexico had "invaded our territory and shed American blood upon the American soil." A joint session of Congress approved the declaration of war, with southern Democrats in strong support because they saw the annexation of Mexico as an opportunity to increase the number of slave states. Sixty-seven Whigs voted against the war on a key slavery amendment, but on the final passage only 14 Whigs voted no, including Reps. Abraham Lincoln and John Quincy Adams. The United States declared war on Mexico on May 13, 1846. Mexico officially declared war on July 7 (sometimes the manifest from President Paredes on May 23 is considered a declaration of war, but only Congress had the power to declare war).

Opposition to the war

In the United States, most Whigs in the North and South opposed the war; most Democrats supported it. Joshua Giddings led a group of dissenters in Washington D.C. He called the war with Mexico "an aggressive, unholy, and unjust war," and voted against supplying soldiers and weapons for the war. He said:

"In the murder of Mexicans upon their own soil, or in robbing them of their country, I can take no part either now or here-after. The guilt of these crimes must rest on others. I will not participate in them."

Fellow Whig, Congressman Abraham Lincoln, contested the causes for the war and demanded to know the exact spot on which Thornton had been attacked and U.S. blood shed. "Show me the spot," he demanded. Whig leader Robert Toombs of Georgia declared:

"This war is a nondescript.... We charge the President with usurping the war-making power... with seizing a country... which had been for centuries, and was then in the possession of the Mexicans.... Let us put a check upon this lust of dominion. We had territory enough, Heaven knew."

Northern abolitionists attacked the war as an attempt by slave-owners -- frequently referred to as "the Slave Power" — to expand the grip of slavery and thus assure their continued influence in the federal government. Acting on his convictions, Henry David Thoreau was jailed for his refusal to pay taxes to support the war, and penned his famous essay, Civil Disobedience.

Former President John Quincy Adams also expressed his belief that the war was fundamentally an effort to expand slavery. In response to such concerns, Democratic Congressman David Wilmot introduced the Wilmot Proviso, which aimed to prohibit slavery in any new territory acquired from Mexico. Wilmot's proposal did not pass Congress, but it spurred further hostility between the factions.

Conduct of the war

After the declaration of war, U.S. forces invaded Mexican territory on two main fronts. The U.S. war department sent a cavalry force under Stephen W. Kearny to invade western Mexico from Fort Leavenworth, reinforced by a Pacific fleet under John D. Sloat. This was done primarily because of concerns that Britain might also attempt to occupy the area. Two more forces, one under John E. Wool and the other under Taylor, were ordered to occupy Mexico as far south as the city of Monterrey.

California

When the US declared war against Mexico, on May 13, 1846, it took almost two months (mid-July 1846) for definite word of war to get to California. U.S. consul Thomas O. Larkin, stationed in Monterey, on hearing rumors of war tried to keep peace between the U.S. and the small Mexican military garrison commanded by José Castro. U.S. Army captain John C. Frémont with about 60 well-armed men had entered California in December 1845 and was making a slow march to Oregon when they received word that war between Mexico and the U.S. was imminent.

On June 15, 1846, some 30 settlers, mostly U.S. citizens, staged a revolt and seized the small Mexican garrison in Sonoma. They raised the "Bear Flag" of the California Republic over Sonoma. It lasted one week until the U.S. Army, led by Frémont, took over on June 23. The California state flag today is based on this original Bear Flag, and still contains the words "California Republic."

Commodore John Drake Sloat, on hearing of imminent war and the revolt in Sonoma, ordered his naval forces to occupy Yerba Buena (present San Francisco) on July 7 and raise the U.S. flag. On July 15, Sloat transferred his command to Commodore Robert F. Stockton, a much more aggressive leader, who put Frémont's forces under his orders. On July 19, Frémont's "California Battalion" swelled to about 160 additional men from newly arrived settlers near Sacramento, and he entered Monterey in a joint operation with some of Stockton's sailors and marines. The word had been received — the war was official. The U.S. forces easily took over the north of California; within days they controlled San Francisco, Sonoma, and Sutter's Fort in Sacramento.

In Northern California, Mexican General José Castro and Governor Pío Pico fled further south into loyalist Mexico. When Stockton's forces, sailing south to San Diego, stopped in San Pedro, he dispatched 50 US Marines, and entered Los Angeles unresisted on August 13, 1846, known as the Siege of Los Angeles, the nearly bloodless conquest of California seemed complete. Stockton, however, left too small a force in Los Angeles, and the Californios, acting on their own and without help from Mexico, led by José Mariá Flores , forced the American garrison to retreat in late September. More than 300 reinforcements sent by Stockton, led by U.S. Navy Captain William Mervine, were repulsed in the Battle of Dominguez Rancho, October 7 through October 9, 1846, near San Pedro, where 14 U.S. Marines were killed. The rancho vaqueros, banded together to defend their land, fighting as Californio Lancers, became a force to deal with the Americans had not planned on. Meanwhile, General Stephen W. Kearny, with a squadron of 139 dragoons, finally reached California after a grueling march across New Mexico, Arizona and the Sonora desert, on December 6, 1846, and was defeated by the Californio Lancers at the Battle of San Pasqual near San Diego, California, where 22 of Kearny's troops were killed.

Stockton rescued Kearny's retreating forces and later, with their re-supplied, combined force, marched north from San Diego, entering the Los Angeles area on January 8, 1847, linking up with Frémont's men. With U.S. forces totaling 660 soldiers and marines, they fought and defeated the 160 man Californio force in the decisive Battle of Rio San Gabriel, and the next day, January 9, 1847, they fought the Battle of La Mesa. On January 12, 1847, the last significant body of Californios surrendered to U.S. forces. That marked the end of the War in California. On January 13, 1847, the Treaty of Cahuenga was signed.

On January 28, 1847, U.S. Army Lieutenant William Tecumseh Sherman and his army unit arrived in Monterey, California as U.S. forces in the pipeline continued to stream into California. On March 15, 1847, Col. Jonathan D. Stevenson’s Seventh Regiment of New York Volunteers of about 900 men started arriving in California. All of these men were in place when word went out that gold was discovered in California, January 1848.

Northeastern Mexico

The defeats at Palo Alto and Resaca de la Palma caused political turmoil in Mexico, turmoil which Antonio López de Santa Anna used to revive his political career and return from self-imposed exile in Cuba. He promised the U.S. troops that if allowed to pass through their blockade, he would negotiate a peaceful conclusion to the war and sell the New Mexico and Alta California territories to the United States. Once he arrived in Mexico, however, he reneged and offered his military skills to the Mexican government. After he had been appointed general he reneged again and seized the presidency.

Led by Taylor, 2,300 U.S. troops crossed the Rio Grande (Rio Bravo) after some initial difficulties in obtaining river transport. He occupied the city of Matamoros, then Camargo (where while waiting the soldiery suffered the first of many problems with disease) and then proceeded south and besieged the city of Monterrey. This Battle of Monterrey was a hard fought battle during which both sides suffered serious losses. The American light artillery was ineffective against the stone fortifications of the city. The Mexican forces were under General Pedro de Ampudia. A U.S. infantry division and the Texas Rangers captured four hills to the west of the town and with them heavy cannon. That lent the U.S. soldiers the strength to storm the city from the west and east. Once in the city, U.S. soldiers fought house to house: each was cleared by throwing lighted shells, which worked like grenades. Eventually, these actions drove and trapped Ampudia's men into the city's central plaza, where howitzer shelling forced Ampudia to negotiate. Taylor agreed to allow the Mexican Army to evacuate and to an 8-week armistice in return for the surrender of the city. Under pressure from Washington, Taylor broke the armistice and occupied the city of Saltillo, southwest of Monterrey. Santa Anna blamed the loss of Monterrey and Saltillo on Ampudia and demoted him to command a small artillery battalion.

On February 22, 1847, Santa Anna personally marched north to fight Taylor with 20,000 men. Taylor, with 4,600 men, had entrenched at a mountain pass called Buena Vista. Santa Anna suffered desertions on the way north and arrived with 15,000 men in a tired state. He demanded and was refused surrender of the U.S. army; he attacked the next morning. Santa Anna flanked the U.S. positions by sending his cavalry and some of his infantry up the steep terrain that made up one side of the pass, while a division of infantry attacked frontally along the road leading to Buena Vista. Furious fighting ensued during which the U.S. troops were almost routed, but were saved by artillery fire against a Mexican advance at close range by Captain Braxton Bragg, and a charge by the mounted Mississippi Riflemen under Jefferson Davis. Having suffered discouraging losses, Santa Anna withdrew that night, leaving Taylor in control of Northern Mexico. Polk distrusted Taylor, whom he felt had shown incompetence in the Battle of Monterrey by agreeing to the armistice, and may have considered him a political rival for the White House. Taylor later used the Battle of Buena Vista as the centerpiece of his successful 1848 presidential campaign.

Scott's campaign

Rather than reinforce Taylor's army for a continued advance, President Polk sent a second army under General Winfield Scott, which was transported to the port of Veracruz by sea, to begin an invasion of the Mexican heartland. Scott performed the first major amphibious landing in the history of the United States in preparation for the Siege of Veracruz. A group of 12,000 volunteer and regular soldiers successfully offloaded supplies, weapons and horses near the walled city. Included in the invading force were Robert E. Lee, George Meade, Ulysses S. Grant, and Thomas "Stonewall" Jackson. The city was defended by Mexican General Juan Morales with 3,400 men. Mortars and naval guns under Commodore Matthew C. Perry were used to reduce the city walls and harass defenders. The city replied as best it could with its own artillery. The effect of the extended barrage destroyed the will of the Mexican side to fight against a numerically superior force, and they surrendered the city after 12 days under siege. U.S. troops suffered 80 casualties, while the Mexican side had around 180 killed and wounded, about half of whom were civilian. During the siege, the U.S. side began to fall victim to yellow fever.

Scott then marched westward toward Mexico City with 8,500 healthy troops, while Santa Anna set up a defensive position in a canyon around the main road at the halfway mark to Mexico City, near the hamlet of Cerro Gordo. Santa Anna had entrenched with 12,000 troops and artillery that were trained on the road, along which he expected Scott to appear. However, Scott had sent 2,600 mounted dragoons ahead, and the Mexican artillery prematurely fired on them and revealed their positions. Instead of taking the main road, Scott's troops trekked through the rough terrain to the north, setting up his artillery on the high ground and quietly flanking the Mexicans. Although by then aware of the positions of U.S. troops, Santa Anna and his troops were unprepared for the onslaught that followed. The Mexican army was routed. The U.S. army suffered 400 casualties, while the Mexicans suffered over 1,000 casualties and 3,000 were taken prisoner.

In May, Scott pushed on to Puebla, the second largest city in Mexico. Because of the citizens' hostility to Santa Anna, the city capitulated without resistance on May 1. Mexico City was laid open in the Battle of Chapultepec and subsequently occupied.

Winfield Scott became an American national hero after his victories in the Mexican-American War, and later became military governor of occupied Mexico City.

Treaty of Guadalupe Hidalgo

Main article: Treaty of Guadalupe Hidalgo

The Treaty of Guadalupe Hidalgo, signed on February 2, 1848 by American diplomat Nicholas Trist, ended the war and gave the U.S undisputed control of Texas, established the U.S.-Mexican border of the Rio Grande River, and ceded to the United States the present-day states of California, Nevada, Utah, and parts of Colorado, Arizona, New Mexico, and Wyoming. In return, Mexico received US $15,000,000, half the amount of money that the U.S. had attempted to offer in return for the Mexican provinces of Nuevo México and Alta California three years earlier. This led a leading U.S. newpaper, the Whig intelligencer to conclude sardonically that;

We take nothing by conquest.... Thank God.

The exchange of land is known as the Mexican Cession. Mexicans living in the conquered lands could choose to return to Mexico or stay and become American citizens. Article X was stricken from the treaty before it was ratified by the U.S. Senate. These articles promised that the United States would recognize Mexican and Spanish land grants.

In 1853, in what became known as the Gadsden Purchase, the United States paid an additional $10 million to Mexico to purchase land in what is now southern Arizona and southern New Mexico for the construction of a southern route for a transcontinental railroad. The purchase was also designed to further compensate Mexico for the lands taken by the U.S. after the War.

Results

Mexico lost more than 500,000 square miles (about 1,300,000 square km) of land, almost half of its territory. The annexed territories contained about 1,000 Mexican families in Alta California and 7,000 in Nuevo México. A few relocated further south in Mexico; the great majority remained in the US. Descendants of these Mexican families have risen to prominence in American life, such as United States Senator Ken Salazar, and his brother, U.S. Rep. John Salazar, both from Colorado.

A month before the end of the war, Polk was criticized in a United States House of Representatives amendment to a bill praising Major General Zachary Taylor for "a war unnecessarily and unconstitutionally begun by the President of the United States." This criticism, in which Congressman Abraham Lincoln played an important role, followed congressional scrutiny of the war's beginnings, including factual challenges to claims made by President Polk . The vote followed party lines, with all Whigs supporting the amendment. Lincoln's attack haunted his future campaigns in the heavily Democratic state of Illinois, and was cited by enemies well into his presidency. The stand did not cost Lincoln his Congressional seat in Illinois' Seventh Congressional District; the district was the only place in Illinois where a Whig could win high office, and party leaders agreed to one-term limits for Whig representatives there. Lincoln was succeeded by a Democrat, but the Seventh Congressional District voted for Zachary Taylor, a Whig, that fall.

In much of the United States, victory and the acquisition of new land brought a surge of patriotism (the country had also acquired the southern half of the Oregon Country in 1846 through a treaty with the United Kingdom). Victory seemed to fulfill citizens' belief in their country's Manifest Destiny. While Whig Ralph Waldo Emerson rejected war "as a means of achieving America's destiny," he accepted that "most of the great results of history are brought about by discreditable means." Although the Whigs had opposed the war, they made Zachary Taylor their presidential candidate in the election of 1848, praising his military performance while muting their criticism of the war itself.

President Ulysses S. Grant, who as a young army office had served in Mexico under General Taylor, recalled in his Memoirs, published in 1885, that

Generally, the officers of the army were indifferent whether the annexation was consummated or not; but not so all of them. For myself, I was bitterly opposed to the measure, and to this day regard the war, which resulted, as one of the most unjust ever waged by a stronger against a weaker nation. It was an instance of a republic following the bad example of European monarchies, in not considering justice in their desire to acquire additional territory. [3]

Grant also expressed the view that the war against Mexico had brought God's punishment on the United States in the form of the American Civil War:

The Southern rebellion was largely the outgrowth of the Mexican war. Nations, like individuals, are punished for their transgressions. We got our punishment in the most sanguinary and expensive war of modern times. [4]

Many of the military leaders on both sides of the American Civil War had fought as junior officers in Mexico, including Grant, George B. McClellan, Ambrose Burnside, Stonewall Jackson, James Longstreet, George Meade, and Robert E. Lee, as well as the future Confederate President Jefferson Davis.

In Mexico City's Chapultepec Park, the Monument to the Heroic Cadets commemorates the heroic sacrifice of six teenaged military cadets who fought to their deaths rather than surrender to American invaders during the Battle of Chapultepec Castle on September 18, 1847. The monument is an important patriotic site in Mexico. On March 5, 1947, nearly one hundred years after the battle, U.S. President Harry S. Truman placed a wreath at the monument and stood for a moment of silence.

Combatants

Although 13,000 U.S. soldiers died during the course of the Mexican War, only about 1,700 were killed in combat. 90% died of disease, such as yellow fever. Mexican casualties are estimated at 25,000.

On the American side, the war was fought by regulars and the volunteers, with the majority of atrocities being committed by volunteers. U.S. soldiers' memoirs describe cases of scalping innocent civilians, the rape and murder of women, the murder of children, the burning of homes, and the desecrating of Catholic religious objects and buildings. One officer's diary records:

"We reached Burrita about 5 pm, many of the Louisiana volunteers were there, a lawless drunken rabble. They had driven away the inhabitants, taken possession of their houses, and were emulating each other in making beasts of themselves.

John L. O'Sullivan, a vocal proponent of Manifest Destiny, later recollected:

"The regulars regarded the volunteers with importance and contempt... [The volunteers] robbed Mexicans of their cattle and corn, stole their fences for firewood, got drunk, and killed several inoffensive inhabitants of the town in the streets."

Many of the volunteers were unwanted and considered poor soldiers. The expression "Just like Gaines's army" came to refer to something useless, the phrase having originated when a group of untrained and unwilling Louisiana troops were rejected and sent back by General Taylor at the beginning of the war.

One of the contributing factors to loss of the war by Mexico was the inferiority of their weapons. The Mexican army was using British muskets from the Napoleonic Wars; furthermore, Mexican troops were trained to fire with their muskets held loosely at hip-level, while U.S. soldiers used the more accurate method of butting the rifle up to the shoulder and taking aim along the barrel. In contrast to the aging Mexican standard-issue infantry weapon, some U.S. troops had the latest U.S.-manufactured breech-loading flintlock "Hall's" rifles and Percussion cap Model 1841 rifles. In the later stages of the war, U.S. cavalry and officers were issued Colt revolvers, of which the U.S. army had ordered 1000 in 1846. Throughout the war, the superiority of the U.S. artillery often carried the day.

Political divisions inside Mexico was another factor in the victory by the United States. Inside Mexico, the centralistas and republicanos vied for power, and at times the two factions inside Mexico's military fought each other rather than the invading American army. Another faction called the monarchists, whose members wanted to install a king(some even advocated rejoining Spain) further complicated matters. This third faction would rise to predominance in the period of the French intervention in Mexico.

The Saint Patrick's Battalion (San Patricios) was a group of several hundred immigrant soldiers, the majority Irish, who deserted the U.S. Army because of ill-treatment or sympathetic leanings to fellow Mexican Catholics. They joined the Mexican army. Most were killed in the Battle of Churubusco; about 100 were captured by the U.S. and roughly half were hanged as deserters.

The last surviving U.S. veteran of the conflict, Owen Thomas Edgar, died on September 3, 1929, at age 98.

Impact of the War in the United States

Despite the objections of the abolitionists, the war received enthusiastic support in all sections of the United States and was fought almost entirely by volunteers. The army swelled from just over 6,000 to more than 115,000. Of this total approximately 1.5 percent were killed in the fighting, and nearly 10 percent died of disease; another 12 percent were wounded or discharged because of disease, or both. For years afterward, Mexican War veterans continued to suffer from the debilitating diseases contracted during the campaigns. The casualty rate was thus easily over 25 percent for the 17 months of the war; the total casualties may have reached 35–40 percent if later injury- and disease-related deaths are added. In this respect the war was proportionately the most deadly in American military history.

During the war political quarrels arose regarding the disposition of conquered Mexico. A strong "All-Mexico" movement urged annexation of the entire territory. Abolitionists opposed that position and fought for the exclusion of slavery from any territory absorbed by the United States. In 1847 the House of Representatives passed the Wilmot Proviso, stipulating that none of the territory acquired should be open to slavery. The Senate avoided the issue, and a late attempt to add it to the Treaty of Guadalupe Hidalgo was defeated.

The Treaty of Guadalupe Hidalgo was the result of Nicholas Trist's unauthorized negotiations. It was approved by the U.S. Senate on 10 March 1848, and ratified by the Mexican Congress on May 25. Mexico's cession of Alta California and Nuevo México and its recognition of U.S. sovereignty over all of Texas north of the Rio Grande formalized the addition of 3.1 million km2 (1.2 million mi2) of territory to the United States. In return the United States agreed to pay $15 million and assumed the claims of its citizens against Mexico. A final territorial adjustment between Mexico and the United States was made by the Gadsden Purchase in 1853.

See also

• Battles of the Mexican War
• History of Mexico
• List of Mexican War Veterans
• Reconquista (Mexico)

References

Primary Sources

• Polk, James. Polk: The Diary of a President, 1845-1849, Covering the Mexican War, the Acquisition of Oregon, and the Conquest of California and the Southwest. edited by Allan Nevins (1929)
• Personal Memoirs of Ulysses S. Grant from Project Gutenberg

Secondary Sources

Surveys

• Bauer K. Jack. The Mexican War, 1846-1848. Macmillan, 1974.
• Crawford, Mark; Heidler, Jeanne T.; Heidler, David Stephen , eds. Encyclopedia of the Mexican War (1999) (ISBN 157607059X)
• De Voto, Bernard, Year of Decision 1846 (1942)
• Mayers, David; Fernández Bravo, Sergio A., "La Guerra Con Mexico Y Los Disidentes Estadunidenses, 1846-1848" [The War with Mexico and US Dissenters, 1846-48]. Secuencia [Mexico] 2004 (59): 32-70. Issn: 0186-0348
• Meed, Douglas. The Mexican War, 1846-1848 (2003). A short survey.
• Rodríguez Díaz, María Del Rosario. "Mexico's Vision of Manifest Destiny During the 1847 War" Journal of Popular Culture 2001 35(2): 41-50. Issn: 0022-3840
• Smith, Justin Harvey. The War with Mexico. 2 vol (1919). Pulitzer Prize winner.
• California History, Bancroft - http://www.1st-hand-history.org/Hhb/HHBindex.htm

Military

• Bauer K. Jack. Zachary Taylor: Soldier, Planter, Statesman of the Old Southwest. Louisiana State University Press, 1985.
• Eisenhower, John. So Far From God: The U.S. War with Mexico, Random House (New York; 1989)
• Frazier, Donald S. The U.S. and Mexico at War, Macmillan (1998)
• Hamilton, Holman, Zachary Taylor: Soldier of the Republic , (1941)
• Johnson, Timothy D. Winfield Scott: The Quest for Military Glory, University Press of Kansas (1998)
• Foos, Paul. A Short, Offhand, Killing Affair: Soldiers and Social Conflict during the Mexican War (2002)
• Lewis, Lloyd. Captain Sam Grant (1950)
• Winders, Richard Price. Mr. Polk's Army Texas A&M Press (College Station, 1997)

Political and Diplomatic

• Albert J. Beveridge; Abraham Lincoln, 1809-1858. Volume: 1. 1928.
• Brack, Gene M. Mexico Views Manifest Destiny, 1821-1846: An Essay on the Origins of the Mexican War (1975).
• Fowler, Will. Tornel and Santa Anna: The Writer and the Caudillo, Mexico, 1795-1853 (2000)
• Gleijeses, Piero. "A Brush with Mexico" Diplomatic History 2005 29(2): 223-254. Issn: 0145-2096 debates in Washington before war
• Graebner, Norman A. Empire on the Pacific: A Study in American Continental Expansion. New York: Ronald Press, 1955.
• Graebner, Norman A. "Lessons of the Mexican War." Pacific Historical Review 47 (1978): 325-42.
• Graebner, Norman A. "The Mexican War: A Study in Causation." Pacific Historical Review 49 (1980): 405-26.
• Krauze, Enrique. Mexico: Biography of Power, Harpers: 1997
• Pletcher David M. The Diplomacy of Annexation: Texas, Oregon, and the Mexican War. University of Missouri Press, 1973.
• Price, Glenn W. Origins of the War with Mexico: The Polk-Stockton Intrigue. University of Texas Press, 1967.
• Robinson, Cecil, The View From Chapultepec: Mexican Writers on the Mexican War, University of Arizona Press (Tucson, 1989)
• Ruiz, Ramon Eduardo. Triumph and Tragedy: A History of the Mexican People, Norton 1992
• Schroeder John H. Mr. Polk's War: American Opposition and Dissent, 1846-1848. University of Wisconsin Press, 1973.
• Sellers Charles G. James K. Polk: Continentalist, 1843-1846 Princeton University Press, 1966.
• Smith, Justin Harvey. The War with Mexico. 2 vol (1919). Pulitzer Prize winner.
• Weinberg Albert K. Manifest Destiny: A Study of Nationalist Expansionism in American History Johns Hopkins University Press, 1935.
• Yanez, Agustin. Santa Anna: Espectro de una sociedad (1996)

External links

• Intervención Norteamericana en México, an account of the war (in Spanish) from the Spanish Wikipedia.
• The Handbook of Texas Online: Mexican War
• The Mexican War
• Mexican War Resources
• The Mexican War and the Media, 1845-1848
• Lone Star Internet
• PBS site of US-Mexican war program
• Treaty of Guadalupe Hidalgo and related resources at the U.S. Library of Congress
• Letters of Winfield Scott including official reports from the front sent to the Secretary of War
• Smithsonian teaching aids for "Establishing Borders: The Expansion of the United States, 1846-48"
• Franklin Pierce's Journal on the March from Vera Cruz
• A History by the Descendants of Mexican War Veterans