A Concise History of the U.S.-Mexican War


Gen. Zachary Taylor

"From your known high character, both as a public officer and private citizen, I was strengthened in my hope that some arrangement could be made by which friendly relations might be maintained on the frontier, until a final settlement of the question of boundary...But if such is not to be the case - if hostilities are to ensue - the responsibility must rest with them who actually commence them."

- Gen. Zachary Taylor
   to Gen. Mariano Arista, April 25, 1846

3. The Northern Campaign

True to his word, General Mariano Arista directed Mexican troops to cross the Rio Grande. On April 25, 1846, at Rancho de Carricitos (about 25 miles northwest of present-day Brownsville), 2,000 men under command of General Torrejon ambushed a squad of U.S. dragoons led by Captain Seth Thornton. During the skirmish which followed, the patrol lost 14 men killed, with the remainder being taken prisoner. Two wounded Americans later died.

General Taylor immediately sent a report of the "Thornton Affair" to President Polk. It was received in Washington on the evening of Saturday, May 9, 1846. After consulting with his cabinet on Sunday, Polk addressed a joint session of the U.S. Congress the following day, proclaiming to the assembled senators and representatives: "American blood has been shed on American soil." Not surprisingly, Polk called for an immediate declaration of war. Two days later, on May 13th, Congress made it official.

In the days immediately following the ambush of Captain Thornton and his men, General Taylor became increasingly troubled by reports that the Mexican army, split into two divisions, had crossed both above and below the fort, with a view to attacking Taylor's vulnerable supply depot at Point Isabel, located on the Texas coast about twenty miles northeast of Fort Texas. Accordingly, on May 1, 1846, Taylor took the bulk of his troops and marched for Point Isabel, arriving there safely on May 3.

On that very same day, taking advantage of General Taylor's absence, the Mexican forces in Matamoros, commanded by General Mejía, began shelling the tiny garrison left behind at Fort Texas. The siege and almost constant bombardment lasted six days. Miraculously, during that time the fort's commander, Major Jacob Brown, and Sergeant Horace Weigart of the 7th Infantry were the only Americans killed.

Although greatly outnumbered and unsure when the rest of the "Army of Occupation" would be able to come to the rescue, the garrison, under command of Captain Edgar Hawkins, who took over after Brown was injured, refused to surrender.

On May 7, after loading a large number of supply wagons, the army set out from Point Isabel to relieve Fort Texas (also called Fort Taylor). The next afternoon, General Taylor found the road to the fort blocked by the Mexican army, under command of General Arista, at a place called Palo Alto, about eight miles north of the Rio Grande. There, the first major battle of the Mexican War took place. Primarily an artillery duel, the engagement resulted in heavy casualties for the Mexicans and the need to pull back t a more easily defensible position. Since they were not driven from the field, the Americans claimed a victory, although it was not a decisive one.

The following day, about three miles north of the river, the two armies met again at Resaca de la Palma. There, the Mexicans were firmly entrenched along a long, shallow stream, hidden in the dense chaparral characteristic of the region. This time both infantry and dragoons were called into play, as well as artillery, and the losses on both sides were much higher than the day before.

In the end, the Mexican army was defeated and driven back to Matamoros. General Arista's victory meal, being prepared at his camp nearby, in anticipation of success, was eaten that evening by American soldiers.

Following their victories at Palo Alto and Resaca de la Palma (and the subsequent relief of Fort Texas), the American army added to its successes with the bloodless occupation of Matamoros on May 18, 1846, after Arista abandoned the town and withdrew his forces to the relative safety of Monterey, about a hundred miles to the south.

During the summer of 1846 the war entered a brief lull while thousands of volunteers, authorized by Congress for twelve-months service, arrived in the lower Rio Grande Valley. At the same time, volunteers initially mustered in for three and six months had to be let go. Taylor, frustrated with the Quartermaster's Department at New Orleans, was unable to move further into Mexico for lack of transportation and supplies. As a result, he and the thousands under his command had to sit and wait until the end of July before they could begin moving upriver to the next staging point, a little Mexican town called Camargo.

By September, although it was necessary to leave a number of troops behind in Camargo, Taylor managed to march a large force to Monterey and lay siege to that city. The fighting was fierce. In the end, it came down to hand-to-hand combat in the city streets. But again, the American army was victorious after the Mexican forces agreed to a capitulation, the terms of which were criticized in the U.S.

During August and September 1846, a second force, made up largely of volunteers, was assembled at San Antonio de Bexar, Texas, under command of General John E. Wool. By the beginning of October, they were on the march into Mexico, to link up with Taylor in Chihuahua.

A third large force, mostly Missouri volunteers under command of Colonel Alexander Doniphan, after helping General Stephen W. Kearney secure Santa Fé, New Mexico in August 1846, began their long march south into Chihuahua. They first fought a battle near present-day Las Cruces, New Mexico, then occupied El Paso del Norte (present-day Ciudad Juarez) before continuing their journey. In February 1847, they were met by a large Mexican force near the Sacramento River in Chihuahua, where a battle ensued and Doniphan's men emerged victorious.

Almost simultaneously, on February 22nd and 23rd, 1847, the American army under command of General Taylor, along with General Wool and his men (who had arrived in Northern Mexico by that time), fought a Mexican force led by General Antonio Lopez de Santa Anna, vastly superior in numbers, near the hacienda of Buena Vista.

The Battle of Buena Vista (or La Angostura, as it is called in Mexico) was one that could have gone either way for the Americans. It was the single bloodiest battle of the war. Hard pressed on all sides, fighting on some of the roughest terrain any army has ever encountered, it appeared for a while that the Mexicans might prevail. But in the end, Santa Anna withdrew, leaving Taylor with yet another victory to his credit. This added to his stature as a candidate for the Presidency of the United States - a position he was to win in the election of 1848.

After Buena Vista, Northern Mexico was relatively quiet as the Mexican army's attention was, of necessity, drawn to the central coast. There, in March 1847, General Winfield Scott's "Army of Invasion," landed at Vera Cruz, the first step towards their ultimate goal: the capital, Mexico City.



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