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


"There shall be firm and universal peace between the United States of America and the Mexican Republic, and between their respective Countries, territories, cities, towns and people, without exception of places or persons."

-- The Treaty of Guadalupe Hidalgo, negotiated by Nicholas Trist, 1848

The Treaty of Guadalupe Hidalgo, 1848

8. The Peace Treaty

Following the American occupation of Mexico City on September 14, 1847, it was expected in the United States that a negotiated peace was not far behind. Unfortunately, that was not to be the case. Mexico's government was in turmoil, with no one willing to immediately come forward and take responsibility for acceding to the American demands, which included not only the recognition of the right of Texas to annex itself to the United States, as well as fixing its boundary at the Rio Grande, but also the cession of New Mexico and both Upper and Lower California - nearly half the territory then claimed by Mexico (but occupied by only about 1% of its population).

The envoy sent by the U.S. government to negotiate a treaty with Mexico was Nicholas Trist, a veteran diplomat who spoke fluent Spanish, the result of an earlier foreign service post Trist held in Cuba. Upon arrival in Mexico in May 1847 Trist encountered two significant difficulties: First, at that time the Mexicans were not disposed to enter into negotiations; and second, Trist and General Scott entered immediately into an unfortunate personal feud that later became an embarrassment to them both when they finally took the time to talk to each other and actually became close friends.

In August, after the Battles of Contreras and Churubusco were fought and won by the American army and Scott's troops were then only a few short miles from the gates of Mexico City, a truce was declared. For several days Trist met with Mexican commissioners José Herrera, Bernardo Couto, Ignacio Mora y Villamil, and Miguel Atristan. However, after General Santa Anna, who was still President at that time, rejected the proposed American terms, hostilities resumed. But the resulting takeover of Mexico City by Scott's army led to Santa Anna's political downfall (and eventual return to exile).

With Santa Anna out of the way, a new Mexican government was formed in November, at the city of Queretaro, under the leadership of Manuel Peña y Peña, Mexico's former foreign minister - a government which was willing to consider the American terms (already well known to the Mexicans as a result of Trist's earlier meetings with Couto, Herrera, and Atristan). But, just as Trist was about to enter into serious negotiations, he received a dispatch recalling him to Washington. Obviously not understanding or appreciating the handicaps Trist had been forced to overcome first, President Polk had grown impatient with his envoy's apparent lack of progress in the six months he'd been in Mexico.

Trist, fearful of losing an opportunity which might not present itself again soon, and urged on not only by General Scott, but also the Mexicans and the British legation in Mexico City, decided to openly ignore the recall and finish the job he'd been sent to do.

Negotiations began in December at the town of Guadalupe Hidalgo, with Trist sitting as the lone American negotiator, facing a trio of Mexican commissioners which included Bernardo Couto and Miguel Atristan, with whom Trist was already acquainted, and Luis Cuevas, another former foreign minister.

The Mexican commissioners were disposed to agree to all the major American demands, save one: The cession of Lower, or Baja, California. This, for whatever reason (and several have been suggested by various historians) they adamantly refused to give up, also demanding that a strip of land, permitting unrestricted passage from Sonora to Baja California, also be included in the treaty. When Trist finally agreed to this concession, after an initial refusal to consider it, the remainder of the negotiations went more quickly. After that, the only other disagreement of any consequence which arose was over whether or not San Diego was located in Upper or Lower California. After much consulting of maps, it was finally agreed to include it in the territory ceded to the United States.

By the end of January 1848, it was apparent to Trist that he had obtained everything Polk wanted, with the exception of Lower California, the cession of which, according to his original instructions, was not as vital to the administration as that of New Mexico and Upper California (for which the U.S. paid $15 million). Taking a firm stance, he pressured the Mexicans to finish up the work they'd begun two months earlier. On February 2, 1848, Trist, along with Couto, Atristan, and Cuevas put his signature on the treaty, which included an additional "secret" article allowing for up to eight months to pass between the time the treaty was signed and the exchange of ratifications by both governments.

Trist immediately dispatched a copy of the treaty to President Polk, which was carried to Washington by James Freaner, a correspondent for the New Orleans Delta, who delivered the precious document to the White House on the evening on February 19, 1848.

Upon learning that the terms of the treaty were in keeping with Trist's original instructions, Polk put aside his anger with Trist for having disobeyed his recall, and recommended that the treaty be forwarded to the Senate for ratification - a recommendation with which all the members of the Cabinet, save James Buchanan, concurred. Regardless, over Buchanan's objections (as he wished) the treaty went to the Senate, where on March 10, 1848, with two amendments, it was approved. Six days later, Polk signed it.

On May 26, 1848, a document called the Protocol of Queretaro, in which the amendments to the original treaty were explained to Mexico, was signed by U.S. envoys Nathan Clifford and Ambrose Sevier and Mexican foreign minister Luis de la Rosa. On May 30th, ratifications of the amended treaty were exchanged in Mexico. On July 4th, President Polk proclaimed the treaty to the people of the United States. Thus was the U.S.-Mexican War formally concluded. By early August, U.S. troops had been completely withdrawn from Mexico.



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