Mexican-American War

MEXICAN-AMERICAN WAR

MEXICAN-AMERICAN WAR (1846–1848). The war's remote causes included diplomatic indiscretions during the first decade of American-Mexican relations, as well as the effects of the Mexican revolutions, during which American citizens suffered physical injury and property losses. Its more immediate cause was the annexation of Texas. The Mexican government refused to recognize Texas as independent or the Rio Grande as an international boundary. It first withdrew its minister from Washington, D.C., and then severed diplomatic relations in March 1845.

President James K. Polk anticipated military action and sent Brigadier General Zachary Taylor with his force from Louisiana to the Nueces River in Texas, but he also sought a diplomatic solution. Recognizing that the chief aim of American foreign policy was the annexation of California, Polk planned to connect with that policy the adjustment of all difficulties with Mexico, including the dispute over jurisdiction in the territory between the Nueces River and the Rio Grande.

In September 1845, assured through a confidential agent that the new Mexican government of José Joaquín Herrera would welcome an American minister, and acting on the suggestion of Secretary of State James Buchanan, Polk appointed John Slidell as envoy-minister on a secret mission to secure California and New Mexico for $15 million to $20 million if possible, or for $40 million if necessary—terms later changed by secret instructions to $5 million for New Mexico and $25 million for California.

Mexico refused to reopen diplomatic relations. In January 1846, after the first news that the Mexican government, under various pretexts, had refused to receive Slidell, partly on the ground that questions of boundary and claims should be separated, Polk ordered Taylor to advance from Corpus Christi, Texas, to the Rio Grande, resulting shortly in conflicts with Mexican troops at the battle of Palo Alto on 8 May and the battle of Resaca de la Palma on 9 May. On 11 May, after arrival of news of the Mexican advance across the Rio Grande and the skirmish with Taylor's troops, Polk submitted to Congress a war message stating that war existed and that it was begun by Mexico on American soil. The United States declared war on 13 May, apparently on the ground that such action was justified by the delinquencies, obstinacy, and hostilities of the Mexican government; and Polk proceeded to formulate plans for military and naval operations to advance his goal of obtaining Mexican acceptance of his overtures for peace negotiations.

The military plans included an expedition under Colonel Stephen W. Kearny to New Mexico and from there to California, supplemented by an expedition to Chihuahua; an advance across the Rio Grande into Mexico by troops under Taylor to occupy the neighboring provinces; and a possible later campaign of invasion of the Mexican interior from Veracruz.

In these plans Polk was largely influenced by assurances received in February from Colonel A. J. Atocha, a friend of Antonio López de Santa Anna, then in exile from Mexico, to the effect that the latter, if aided in plans to return from Havana, Cuba, to Mexico, would recover his Mexican leadership and cooperate in a peaceful arrangement to cede Mexican territory to the United States. In June, Polk entered into negotiations with Santa Anna through a brother of Slidell, receiving verification of Atocha's assurances. Polk had already sent a confidential order to Commodore David Conner, who on 16 August permitted Santa Anna to pass through the coast blockade to Veracruz. Having arrived in Mexico, Santa Anna promptly began his program, which resulted in his own quick

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restoration to power. He gave no evidences whatever of his professed pacific intentions.

On 3 July 1846 the small expedition under Kearny received orders to go via the Santa Fe Trail from Fort Leavenworth, Kansas, to occupy New Mexico. It reached Santa Fe on 18 August, and a part of the force (300 men) led by Kearny marched to the Pacific at San Diego. From there it arrived at Los Angeles to join the forces led by Commodore Robert Field Stockton, including John Charles Frémont's Bear Flag insurgents. Kearny and Stockton joined forces and defeated the Mexican army at Los Angeles on 8 and 9 January 1847. On 13 January, Frémont and Andres Pico, the leader of the Mexican forces in California, signed the Treaty of Cahuenga. Kearny went on to establish a civil government in California on 1 March.

Taylor's forces, meanwhile, began to cross the Rio Grande to Matamoros on 18 May 1846 and advanced to the strongly fortified city of Monterrey, which after an attack was evacuated by Mexican forces on 28 September. Later, in February 1847 at Buena Vista, Taylor stubbornly resisted and defeated the attack of Santa Anna's Mexican relief expedition.

Soon thereafter the theater of war shifted to Veracruz, from which the direct route to the Mexican capital seemed to present less difficulty than the northern route. In deciding on the campaign from Veracruz to Mexico City, Polk probably was influenced by the news of U.S. occupation of California, which reached him on 1 September 1846. The U.S. Navy had helped secure Monterrey, San Diego, and San Francisco in California and had continued blockades against Veracruz and Tampico. The Navy provided valuable assistance again when General Winfield Scott began a siege of Veracruz. After the capture of the fortress of Veracruz on 29 March 1847, Scott led the army westward via Jalapa to Pueblo, which he entered on 15 May and from which he began his advance to the mountain pass of Cerro Gordo on 7 August.

Coincident with Scott's operations against Veracruz, Polk began new peace negotiations with Mexico through a "profoundly secret mission." On 15 April, Buchanan had sent Nicholas P. Trist as a confidential peace agent to accompany Scott's army. In August, after the battles of Contreras and Churubusco, Trist arranged an armistice through Scott as a preliminary step for a diplomatic conference to discuss peace terms—a conference that began

on 27 August and closed on 7 September by Mexican rejection of the terms offered. Scott promptly resumed his advance. After hard fighting from 7 to 11 September at the battles of Molino del Rey and Chapultepec, he captured Mexico City on 14 September and with his staff entered the palace, over which he hoisted the American flag.

Practically, the war was ended. Santa Anna, after resigning his presidential office, made an unsuccessful attempt to strike at the American garrison Scott had left at Pueblo, but he was driven off and obliged to flee from Mexico.

The chief remaining American problem was to find a government with enough power to negotiate a peace treaty to prevent the danger of American annexation of all Mexico. Fortunately, Trist was still with the army and in close touch with the situation at the captured capital. Although recalled, he determined to assume the responsibility of remaining to renew efforts to conclude a peace treaty even at the risk of disavowal by his government. After some delay, he was able to conclude with the Mexican commissioners a treaty in accord with the instructions that had been annulled by his recall. The chief negotiations were conducted at Mexico City, but the treaty was completed and signed on 2 February 1848 at the neighboring town of Guadalupe Hidalgo. By its terms, which provided for cessation of hostilities, the United States agreed to pay $15 million for New Mexico and California. Polk received the treaty on 19 February and promptly decided to submit it to the Senate, which approved it on 10 March by a vote of thirty-eight to fourteen. Ratifications were exchanged on 30 May 1848.

Among the chief results of the war were expansion of American territory; a new population called Mexican Americans; increased American interest in the problems of the Caribbean and the Pacific and in the opening and control of isthmian interoceanic transit routes at Panama, Nicaragua, and Tehuantepec; and outbursts of "manifest destiny" from 1848 to 1860. The acquisition of Mexico's northern lands also intensified debates over the extension of slavery into new territory and brought the Union a step closer to war.

BIBLIOGRAPHY

Connor, Seymour V., and Odie B. Faulk. North America Divided: The Mexican War, 1846–1848. New York: Oxford University Press, 1971.

Johannsen, Robert W. To the Halls of the Montezumas: The Mexican War in the American Imagination. New York: Oxford University Press, 1985.

McCaffrey, James M. Army of Manifest Destiny: The American Soldier in the Mexican War, 1846 –1848. New York: New York University Press, 1992.

Robinson, Cecil, ed. and trans. The View from Chapultepec: Mexican Writers on the Mexican-American War. Tucson: University of Arizona Press, 1989.

Smith, George W., and Charles Judah, eds. Chronicles of the Gringos: The United States Army in the Mexican War, 1846–1848. Albuquerque: University of New Mexico Press, 1968.

J. M. Callahan / f. b.

See also Hispanic Americans ; Kearny's March to California ; Manifest Destiny ; Navy, United States ; and vol. 9: Memories of the North American Invasion ; Mexican Minister of War's Reply to Manuel de la Peña y Peña ; National Songs, Ballads, and Other Patriotic Poetry, Chiefly Relating to the War of 1846 ; Message on the War with Mexico .