History Timeline 1840s

Above Photo: Bezaleel W. Armstrong, circa 1846. 2nd Lt., 1st and 2nd Dragoons. Served in the Mexican War at Vera Cruz and Mexico City. Right: Independence Rock on the Oregon Trail in Wyoming. Photo from Hayden Survey, William H. Jackson, 1870. Courtesy National Archives.

Oregon Trail

U.S. Timeline - The 1840s

The Mexican War

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  • Timeline

  • 1846 - Detail

    July 28, 1846 - The Army of the West, under the command of Brigadier General Stephen Watts Kearny, travel down the Santa Fe Trail and arrive at Bent's Old Fort en route to the conquest of New Mexico.

    Bent's Old Fort and General Kearny

    The first battles of the Mexican War had been let, with the initial, known as the Thornton Skirmish, occurring on April 25, 1846 in territory still claimed by Mexico as Mexican Texas. Mexico, chuffed by the agreed annexation of Texas by the United States the year before, was anxious for battle. They would get it. War had been declared in May by President Polk after three additional battles in Texas, and the United States was preparing to send additional troops into Mexican territory as summer approached. General Stephen Watts Kearny was headquartered at Fort Leavenworth, Kansas, with over one thousand seven hundred troops, soon to be extended to two thousand five hundred. The Army of the West would include his own 1st Dragoons. On June 3, 1846, Colonel Kearny received his orders from the Secretary of War, W.L. Marcy.

    Orders to General Kearny, June 3, 1846

    SIR: I herewith send you a copy of my letter to the governor of Missouri for an additional force of one thousand mounted men.

    The object of thus adding to the force under your command is not, as you will percieve, fully set forth in that letter, for the reason that it is deemed prudent that it should not, at this time, become a matter of public notoriety; but to you it is proper and necessary that it should be stated.

    It has been decided by the President to be of the greatest importance in the pending war with Mexico to take the earliest possession of Upper California. An expedition with that view is hereby ordered, and you are designated to command it. To enable you to be in sufficient force to conduct it successfully this additional force of a thousand mounted men has been provided, to follow you in the direction of Santa Fe', to be under your orders, or the officer you may leave in command at Santa Fe'.

    It cannot be determined how far this additional force will be behind that designed for the Santa Fe' expedition, but it will not probably be more than a few weeks. When you arrive at Santa Fe' with the force already called, and shall have taken possession of it, you may find yourself in a condition to garrison it with a small part of your command, (as the additional force will soon be at that place,) and with the remainder press forward to California. In that case you will make such arrangements, as to being followed by the reinforcements before mentioned, as in your judgment may be deemed safe and prudent. I need not say to you that, in case you conquer Santa Fe', (and with it will be included the department or State of New Mexico,) it will be important to provide for retaining safe possession of it. Should you deem it prudent to have still more troops for the accomplishment of the objects herein designated, you will lose no time in communicating your opinion on that point, and all others connect with the enterprise, to this department. Indeed, you are hereby authorized to make a direct requisition for it upon the governor of Missouri.

    It is known that a large body of Mormon emigrants are en route to California, for the purpose of settling in that country. You are desired to use all proper means to have a good understand with them, to the end that the United States may have their co-operation in taking possession of, and holding, that country. It has been suggested here that many of these Mormons would willingly enter into the service of the United States, and aid us in our expedition against California. You are hereby authorized to muster into service such as can be induced to volunteer; not, however, to a number exceeding one-third of your entire force. Should they enter the service they will be paid as other volunteers, and you can allow to designate, so far as it can be properly done, the persons to act as officers thereof. It is understood that a considerable number of American citizens are now settled on the Sacramento River, near Suter's establishment, called "Neuva Helvetia," who are well disposed toward the United States. Should you, on your arrival in the country, find this to be the true state of things there, you are authorized to organize and receive into the service of the United States such portion of these citizens as you may think useful to aid you to hold the possession of the country. You will, in that case, allow them, so far as you shall judge proper, to select their own officers. A large discretionary power is invested in you in regard to these matters, as well as to all others in relation to the expeditions confided to your command.

    The choice of routes be which you will enter California will be left to your better knowledge and ampler means of getting accurate information. We are assured that a southern route (called the Caravan route, by which the wild horses are brought from that country into New Mexico) is practicable; and it is suggested as not improbable that it can be passed over in the winter months, or at least late in autumn. It is hoped that this information may prove to be correct.

    In regard to the routes, the practicability of procuring needful supplies for men and animals, and transporting baggage, is a point to be well considered. Should the President be disappointed in his cherished hope, that you will be able to reach the interior of Upper California before winter, you are then desired to make the best arrangement you can for sustaining your forces during the winter, and for an early movement in the spring. Though it is very desirable that the expedition should reach California this season, (and the President does not doubt you will make every possible effort to accomplish this object,) yet, if in your judgment it cannot be undertaken with a reasonable prospect of success, you will defer it, as above suggested, until spring. You are left unembarrassed by any specific directions in this matter.

    It is expected that the naval forces of the United States, which are now, or will soon be in the Pacific, will be in possession of all the towns of the sea coast, and will co-operate with you in the conquest of California. Arms, ordnance, munitions of war, and provisions, to be used in that country, will be sent by sea to our squadron in the Pacific for the use of the land forces.

    Should you conquer and take possession of New Mexico and Upper California, or considerable places in either, you will establish temporary civil governments therein - abolishing all arbitrary restrictions that may exist, so far as it may be done with safety. In performing this duty it would be wise and prudent to continue in their employment all such of the existing officers as are known to be friendly to the United States, and will take the oath of allegiance to them. The duties at the custom-houses ought, at once, to be reduced to such a rate as may be barely sufficient to maintain the necessary officers, without yielding any revenue to the government. You may assure the people of those provinces that it is the wish and design of the United States to provide for them a free government, with the least possible delay, similar to that which exists in our Territories. They will then be called on to exercise the rights of freemen in electing their own representatives to the territorial legislature. It is foreseen that what relates to the civil government will be a difficult and unpleasant part of your duty, and much must necessarily be left to your own discretion.

    In your whole conduct you will act in such a manner as best to conciliate the inhabitants, and render them friendly to the United States.

    It is desirable that the usual trade between the citizens of the United State and the Mexican provinces should be continued, as far as practicable, under the changed condition of things between the two countries. In consequence of extending your expedition into California, it may be proper that you should increase your supply for goods to be distributed as present to the Indians. The United States superintendent of Indian affairs in St. Louis will aid you in procuring these goods. You will be furnished with a proclamation in the Spanish language, to be issued by you, and circulated among the Mexican people on your entering into or approaching their country. You will use your utmost endearvors to have the pledges and promises therein contained carried out to the utmost extant.

    I am directed by the President to say that the rank of brevet brigadier general will be conferred on you as soon as you commence your movement towards California, and sent round to you by sea, or over the country, or to the care of the commandant of our squadron in the Pacific. In that way cannon, arms, ammmunition, and supplies for the land forces will be sent to you.

    Very respectfully, your obedient servant,

    W.L. MARCH
    Secretary of War

    Colonel S.W. KEARNY,
    Fort Leavenworth, Missouri

    By the end of June 1846, Kearny, now a Brigadier General as conferred by the Secretary of War and President Polk, and his soldiers left Fort Leavenworth, heading toward Bent's Old Fort along the Santa Fe Trail in today's Colorado.

    Kearny and his 1st Dragoon cavalry troops were experienced, two hundred and fifty of them having spent ninety-nine days traveling two thousand miles from Fort Leavenworth on a reconnaissance of the Rocky Mountains up to the South Pass of the Continental Divide from May to August of 1845. This Army of the West would include them, plus one thousand seven hundred men from Volunteer Corps at Fort Leavenworth and five hundred of the Mormon Battalion.

    On July 28, 1846, the Army of the West arrived at Bent's Old Fort. Bent's Old Fort had been established in 1933 by William Bent, Charles Bent, and Ceran St. Vrain to serve as a trading post with local Indians and fur trappers. It is located on the north branch of the Santa Fe Trail. They had, over the first decade, created a trading empire that reached to Fort St. Vrain, Fort Adobe, and company stores in Santa Fe and Taos. It was the only white settlement between Missouri and the towns controlled by Mexico.

    Kearny's arrival at the fort provided the U.S. Army with a stable staging ground for attacks to take control of New Mexico and Mexican territory, California, to the west. His scouts warned Kearny that the battles to take New Mexico would be difficult, however, the Battle of Santa Fe would show that those predictions were inaccurate.

    Kearny and the Battle of Santa Fe

    The Army of the West spent several days at the Bent's Old Fort before preparing to move south. The town of Santa Fe was nearly three hundred miles from the fort. It was commanded by Colonel Diego Achuleta and administered by Mexican Governor Manuel Armijo. Armijo, with the United States troops likely amounting to a force larger than the Mexican militia (the Mexican militia number is not known), did not want to fight, but eventually was convinced by the Catholic priets, Archuleta, and other Mexican Army officers that they should defend the city.

    On August 9, 1846, they mounted a defensive position in Apache Canyon, ten miles southeast of the city. Six days later with the majority of the American Army of the West approaching closer, Governor Armijo changed his mind. He dismissed Archuleta and fled to Chihuahua. The Mexican Militia retreated. There are some who contend that an American, James MaGoffin, had convinced Armijo and Archuleta to retreat, perhaps with a bribe. That story is unverified.

    On August 15, 1846, General Kearny and the Army of the West arrived in Santa Fe with no resistance. He claimed New Mexico Territory for the United States and established himself the Military Governor on August 18. Later, Kearny organized a civilian government to maintain order and left behind a sufficient force to enable that while he continued on the mission that President Polk and Secretary of War Marcy had directed in his orders. Kearny and the Army of the West moved into California.

    Bent's Old Fort Today

    Today you can visit a reconstruction of Bent's Old Fort, which is a National Historic Site administered by the National Park Service. It is located at 35110 State Highway 194 E. La Junta, Colorado, 81050, and is open year round with a Visitor Center, the reconstructed fort, hiking trail, an orientation film, "Traders, Tribes, and Travelers," and guided or self-guided tours.

    Image above: Montage of two images, Bent's Old Fort (background), 2015, Carol M. Highsmith, and (inset right) engraving of General Stephen Kearny, circa 1846, T.B. Welch. Both images courtesy Library of Congress. Below: Lithograph of the Army of the West, Mouth of Night Creek, 1848, William H. Emory. Courtesy Library of Congress. Information Source: National Park Service; Wikipedia Commons.

    Army of the West, Southwest USA

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