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


"The undersigned enters New Mexico with a large military force for the purpose of seeking union with and ameliorating the condition of its inhabitants...It is enjoined on the citizens of New Mexico to remain quietly at their homes, and to pursue their peaceful avocations. So long as they continue in such pursuits, they will not be interfered with by the American army, but will be respected and protected in their rights, both civil and religious."

- Gen. Stephen W. Kearny
   July 31, 1846

Gen. Stephen Watts Kearny

5. The Occupation of New Mexico

In 1846 the United States claimed as its territory the land between the Nueces River and the Rio Grande, by virtue of prior claim by the newly-annexed Republic of Texas. By the same token, so too did it maintain that the annexation of Texas gave the U.S. title to what is now the eastern half of present-day New Mexico.

Accordingly, just as General Zachary Taylor had been sent to the assert American sovereignty over the "Nueces Strip," so too was Colonel (soon to be Brevet Brigadier-General), Stephen Watts Kearney, sent to occupy New Mexico. Unlike Taylor, Kearney had not one, but two missions: First, secure New Mexico; Second, continue westward and conquer Upper California. This was a land, according to Secretary of War William L. Marcy, where the people, particularly the American settlers residing in the Sacramento River valley, were "well disposed towards the United States."

Kearney was at Fort Leavenworth when he received his orders in June 1846. At that time he was assured the state of Missouri was raising a volunteer force to supplement the regulars under his command. Secretary Marcy also instructed him to try to enlist, from among the Mormon emigrants then temporarily settled in the Iowa Territory, "a number [not] exceeding one-third of your entire force" in order "to aid us in our expedition against California." To do this Kearney sent Capt. James Allen, of the First Dragoons, to the Mormon camps. There, the persuasive Allen was successful in raising an entire battalion.

In June, before Allen was able to join him with his newly-raised "Mormon Battalion," Kearney set out from Fort Leavenworth with a large force numbering 1,558 men. This so-called "Army of the West" was made up of a battalion of Missouri Mounted Volunteers, five squadrons of the First Dragoons, and the First Regiment of Missouri Mounted Volunteers, led by Colonel Alexander Doniphan. Kearney's forces were also accompanied by a group of Indian guides, a French interpreter, and a small party of U.S. Army topographical engineers under command of Lt. William H. Emory.

Following the well-worn Santa Fé Trail, used by traders from Missouri for over two decades, Kearney's forces marched and rode across the vast open plains of what was then called the "Great American Desert." Along the way, they marveled at the prairie's lack of trees and the vast herds of wild bison they encountered.

Near the end of July they reached Bent's Fort, a private, fortified trading post located in present-day southern Colorado. There, on July 31st, Kearney issued a proclamation, in advance of entering New Mexico, in which he announced he was at the head of a large military force which intended to occupy that department for the purpose of "seeking union with and ameliorating the condition of its inhabitants." The Mexican governor of New Mexico, General Manuel Armijo, learning that Kearney was on the march and of his pronouncement at Bent's Fort, responded on August 8th by issuing his own proclamation at Santa Fé, in which he declared he was "willing to sacrifice his life and all his interests in the defense of his country."

Hoping to take New Mexico without shedding blood, Kearney sent out from Bent's Fort, ahead of his main force, James W. Magoffin, a veteran Santa Fé trader. He was accompanied by Lt. Philip St. George Cooke and a small dragoon escort. At Santa Fé Cooke was received publicly by Armijo, who later that night met secretly with both Cooke and Magoffin. During this meeting, Cooke later wrote, he was made to understand Governor Armijo's "disinclination to actual resistance." Whether or not this means Armijo was bribed, as some historians have maintained, is uncertain. However, by the time Kearney's forces reached the mountain pass near Santa Fé, where a New Mexican force, said to have numbered 4,000 men was supposed to have assembled to resist the American advance, Armijo's army had disappeared - along with the governor himself. On August 18, 1846, the "Army of the West" was able to ride unopposed into Santa Fé and take possession of the capital without firing a shot.

Kearney's first official act, after headquartering himself in the old Spanish governor's palace recently vacated by Armijo, was to issue a proclamation declaring that New Mexico was now part of the United States. A few days later he issued orders for the building of an adobe-brick fortress, to be constructed on a hill overlooking the town. Completed about a month later, it was called Fort Marcy in honor of the U.S. Secretary of the War. Finally, after establishing a civil government, with Charles Bent as first American governor of the "Territory of New Mexico," he set out for California. Kearney departed on September 25th with 300 U.S. dragoons, leaving Colonel Alexander Doniphan in charge of the military forces - with Doniphan to hand over command to Colonel Sterling Price upon his arrival with the Second Missouri Mounted Volunteers.

After Price arrived in October, Doniphan and his men headed south for Mexico, under orders to rendezvous with General Wool in Chihuahua. Along the way, they fought both Indians and Mexicans. On Christmas Day 1846, they battled a large Mexican force which had ridden out from El Paso del Norte (present-day Ciudad Juarez) in a vain attempt to stop the determined Missourians. The ensuing clash was called the Battle of El Brazito.

In the meantime, some native New Mexicans, both those of Spanish ancestry as well as full-blooded Pueblo Indians, began to regret that nothing had been done to try to stop the American advance. Determined to do something, a plot was hatched which called for a Christmas uprising. But the plot was found out when a handful of New Mexican women confided in the authorities.

Because its primary leaders got away, the planned uprising was merely postponed, not cancelled, despite Governor Bent's January 5, 1847 plea for domestic tranquility. Tragically, only two weeks later, at his home in Don Fernando de Taos (present-day Taos, New Mexico), the governor was brutally murdered in front of his family. At the same time, several other government officials were also surprised and killed by the rebels. "It appeared," wrote Col. Sterling Price, "to be the object of the insurrectionists to put to death every American and every Mexican who had accepted office under the American government."

The Americans moved quickly to put down the rebellion. At Mora, a force led by Captain Israel Hendley was successful in dealing a lethal hand to the insurrectionists while Price himself led his troops into battle at La Cañada, Embudo Pass and Pueblo de Taos.

At the latter place, the rebels crowded into the old Spanish mission church, a large building constructed of thick adobe bricks. There, they were determined to make a stand. During the two-day battle which followed, its defenders were killed in large numbers by the Americans, who used their artillery to blast gaping holes in the adobe walls. The ruins of the old church still stand today on the grounds of the ancient pueblo.

After the January 1847 uprising was quelled, New Mexico was relatively quiet for the remainder of the war. Only a few minor incidents marred the peace.



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