This treaty that concluded the Mexican War settled the most contentious disagreements between the United States and Mexico and added California and most of the Southwest to U.S. territory.

Drafted and signed at the Mexican village of Guadalupe Hidalgo, near Mexico City, on February 2, 1848, the Treaty of Guadalupe Hidalgo ended the Mexican War (1846-1848). The war had been prompted partly by hawkish American adherents of manifest destiny Manifest destiny;and Mexico[Mexico] , a belief in the almost inevitable expansion of the United States through the whole of North America. However, the conflict itself had been triggered in U.S.-Mexican clashes over disputed territories shortly after the United States annexed Texas;annexation by United States the Republic of Texas in 1845. The specific cause of the war was the dispute over which river—the Rio Bravo del Norte or the Nueces—marked a boundary line between the two countries. War was declared formally in April of 1846, after Mexican and U.S. troops clashed in the disputed territory between the two rivers. Guadalupe Hidalgo, Treaty of (1848)
Mexican War (1846-1848);Treaty of Guadalupe Hidalgo (1848)
Mexico;and United States[United States]
Santa Anna, Antonio López de
Bravo, Nicolás
[kw]Treaty of Guadalupe Hidalgo Ends Mexican War (Feb. 2, 1848)
[kw]Guadalupe Hidalgo Ends Mexican War, Treaty of (Feb. 2, 1848)
[kw]Hidalgo Ends Mexican War, Treaty of Guadalupe (Feb. 2, 1848)
[kw]Ends Mexican War, Treaty of Guadalupe Hidalgo (Feb. 2, 1848)
[kw]Mexican War, Treaty of Guadalupe Hidalgo Ends (Feb. 2, 1848)
[kw]War, Treaty of Guadalupe Hidalgo Ends Mexican (Feb. 2, 1848)
Guadalupe Hidalgo, Treaty of (1848)
Mexican War (1846-1848);Treaty of Guadalupe Hidalgo (1848)
Mexico;and United States[United States]
Santa Anna, Antonio López de
Bravo, Nicolás
[g]Mexico;Feb. 2, 1848: Treaty of Guadalupe Hidalgo Ends Mexican War[2590]
[g]Central America and the Caribbean;Feb. 2, 1848: Treaty of Guadalupe Hidalgo Ends Mexican War[2590]
[g]United States;Feb. 2, 1848: Treaty of Guadalupe Hidalgo Ends Mexican War[2590]
[c]Diplomacy and international relations;Feb. 2, 1848: Treaty of Guadalupe Hidalgo Ends Mexican War[2590]
[c]Wars, uprisings, and civil unrest;Feb. 2, 1848: Treaty of Guadalupe Hidalgo Ends Mexican War[2590]
Polk, James K.
[p]Polk, James K.;and Mexican War[Mexican War]
Buchanan, James
[p]Buchanan, James;and Mexican War[Mexican War]
Trist, Nicholas
Peña y Peña, Manuel de la
Scott, Winfield
[p]Scott, Winfield;and Mexican War[Mexican War]
Taylor, Zachary
[p]Taylor, Zachary;and Mexican War[Mexican War]

In Mexico, political turmoil and poor military strategy and preparedness at first led to fairly easy U.S. victories. Successful campaigns in northeastern Mexico by General Zachary Taylor Taylor, Zachary
[p]Taylor, Zachary;and Mexican War[Mexican War] caused the collapse of the Mexican government and the recall from exile of General Antonio López de Santa Anna, who fought a close but losing battle against Taylor at Buena Vista in February of 1847. The tide turned fully against Mexico after General Winfield Scott Scott, Winfield
[p]Scott, Winfield;and Mexican War[Mexican War] landed an army at Veracruz and fought his way inland against tough resistance to capture Mexico City Mexico City;U.S. occupation of . The crucial battle in Scott’s march from the sea was fought against Santa Anna at Cerro Gordo on April 18, 1847. However, even with Santa Anna’s defeat, Scott’s army had to overcome many difficulties, and it was not until September 14, 1847, that his troops entered and took control of the Mexican capital.

Threatened with impeachment for his conduct of the war, Santa Anna again went into exile. Earlier, when he had taken direct command of the Mexican armed forces, he had named Manuel de la Peña y Peña Peña y Peña, Manuel de la as interim president; he eventually had to ask the Peña government for permission to leave Mexico. Thus, it was Peña’s administration that was forced to agree to the terms of the Treaty of Guadalupe Hidalgo, which were negotiated under the weakest possible conditions for Mexico. In return for a cash payment of $15 million and another $3.25 million in claims of Mexican citizens, Mexico ceded to the United States the territories of New Mexico New Mexico;and Mexican War[Mexican War] and Upper California. California;and Mexican War[Mexican War] The agreement also established the U.S.-Mexican boundary, which followed the course of the Rio Grande Rio Grande from the Gulf of Mexico to the southern border of New Mexico, west to the Gila and Colorado Rivers, Colorado River and eventually to a point just south of San Diego on the Pacific Ocean.

American and Mexican troops face off in the Battle of Buena Vista.

(Library of Congress)

The negotiations leading up to the treaty were complex. In April of 1847, President James K. Polk Polk, James K.
[p]Polk, James K.;and Mexican War[Mexican War] had sent Nicholas Trist Trist, Nicholas of the Department of State to Scott’s camp with a secret treaty proposal drafted by Secretary of State James Buchanan Buchanan, James
[p]Buchanan, James;and Mexican War[Mexican War] . Trist was empowered to consider counterproposals and secure an armistice, which was actually arranged in late August of that same year. Scott Scott, Winfield
[p]Scott, Winfield;and Mexican War[Mexican War] had been in secret communication with Santa Anna, who, without the knowledge of the Mexican government, was trying to arrange treaty terms on his own. Santa Anna assured Scott that hostilities could be suspended and a treaty negotiated if and when Scott’s army laid siege to Mexico City Mexico City;U.S. occupation of . Scott even wrote a memorandum in which he avowed that he would fight a battle in view of the capital and then “give those in the City an opportunity to save the capital by making a peace.”

With victories at Contreras and Churubusco in August, 1847, Scott met Santa Anna’s conditions. The road to Mexico City was open, and the remnants of Santa Anna’s army were put to disordered flight, taking refuge within the capital. Scott was certain that a peace with a compliant Santa Anna could be quickly negotiated. However, Santa Anna was as deceitful and crafty as Scott was forthright and naïve. He knew that Scott’s army was wracked by disease, declining morale, and logistics problems, and he believed that time was his invisible ally. As his blame-shifting maneuvers made clear, he also wanted to avoid making any treaty concessions that would tarnish his national image. Thus, although a cease-fire was arranged, the efforts to draft a mutually acceptable set of terms at the ensuing peace conference proved futile and were probably doomed from the outset. The armistice broke off on September 6, and on September 14 Scott Scott, Winfield
[p]Scott, Winfield;and Mexican War[Mexican War] took Mexico City. By then, Santa Anna had already fled.

When it became clear to Buchanan Buchanan, James
[p]Buchanan, James;and Mexican War[Mexican War] and Polk Polk, James K.
[p]Polk, James K.;and Mexican War[Mexican War] that Santa Anna was stalling, President Polk ordered the recall of Trist, in part to counteract the impression that the United States was eager to achieve a peace, a view gaining currency among the Mexican people. Trist did not return, however; he stayed on after the futile negotiations broke off and fighting resumed. The war dragged on past the departure of Santa Anna, who met his final defeat at Puebla on October 11. It was abundantly clear that Mexico could not reverse the trend of the war, and within two months, it sued for peace. Trist Trist, Nicholas , who had never returned home, became the chief U.S. negotiator at Guadalupe Hidalgo, where the treaty was finally signed.

The draft terms of the treaty, which were ready on January 24, 1848, more fully realized the territorial ambitions of the United States than the terms discussed during the earlier armistice conference, which had left open the Texas border question. However, even from the outset of the earlier negotiations, it had been clear that the United States was determined to annex both Upper California California;and Mexican War[Mexican War] and New Mexico New Mexico;and Mexican War[Mexican War] . In the end, Santa Anna’s delaying tactics had proved a bit more costly to Mexico.

Because a flawed map was used during the treaty negotiations, the boundaries between Mexico and the United States remained open to interpretation. Surveyors could not agree on the identity of the first branch of the Gila River, one of the important demarcation lines, and the boundary line between Mexico and the United States in the area separating the Gila River and the Rio Grande Rio Grande was not settled. However, both the Rio Grande and the Gila River were established as principal boundaries. Mexico thereby ceded territories south of the Nueces River and all of Upper California from one nautical league south of San Diego to the Northwest Territory Northwest Territory . The United States gained all of the Territory of New Mexico—which included most of present Arizona Arizona;and Mexican War[Mexican War] —the disputed lands in southern Texas, and Upper California. In consideration for ceding this vast acreage, the United States was to pay only the stipulated $15 million dollars to the Mexican government and the $3.25 million in private claims. It was a grand bargain for the expansionist believers in manifest destiny Manifest destiny;and Mexico[Mexico] . The treaty terms were quickly accepted by Polk and, with some amendments, ratified by the U.S. Senate on March 10, 1848. Polk, James K.
[p]Polk, James K.;and Mexican War[Mexican War]

The Treaty of Guadalupe Hidalgo did not immediately end the boundary issue. In 1853, during the administration of Franklin Pierce, the final border Borders, U.S.;with Mexico[Mexico] between Mexico and the United States was finally set when the United States purchased the remaining parts of present Arizona and New Mexico from Mexico in the Gadsden Purchase and described the boundary line between the two countries in the disputed area.

An important provision of the Treaty of Guadalupe Hidalgo, article 7, granted U.S. citizenship Citizenship, U.S.;and Mexican War[Mexican War] with full constitutional rights to the Mexicans living in the ceded territories and guaranteed them the titles of their land. However, through the invalidation of Spanish and Mexican land grants, federal courts and the U.S. Congress allowed government agencies, ranchers, land speculators, and business and railroad magnates to gobble up acreage that, by the terms of the treaty, rightly belonged to Mexican Americans. Over two generations, almost twenty million acres of their land was lost to private owners and state and federal agencies.

• Brack, Gene M. Mexico Views Manifest Destiny, 1821-1846: An Essay on the Origins of the Mexican War. Albuquerque: University of New Mexico Press, 1975. Concise investigation of the growth of anti-American sentiment in Mexico on the path toward hostilities.
• Eisenhower, John S. D. Agent of Destiny: The Life and Times of General Winfield Scott. New York: Free Press, 1997. Biography of one of the main American army commanders during the Mexican War by a military historian who closely analyzes Scott’s military actions and the politics behind them.
• McAfee, Ward, and J. Cordell Robinson, comps. Origins of the Mexican War: A Documentary Source Book. 2 vols. Salisbury, N.C.: Documentary Publications, 1982. Useful collection of original documents pertaining to the Mexican War that is especially helpful for research projects.
• Mahin, Dean B. Olive Branch and Sword: The United States and Mexico, 1845-1848. Jefferson, N.C.: McFarland, 1997. Diplomatic history of the Mexican War that concentrates on the policies of the Polk administration and the negotiations of American diplomat Nicholas Trist.
• Pletcher, David M. The Diplomacy of Annexation: Texas, Oregon, and the Mexican War. Columbia: University of Missouri Press, 1973. One of the best studies on U.S. expansionism, this book has a section on the Mexican War that provides a fair and balanced discussion.
• Scheina, Robert L. Santa Anna: A Curse upon Mexico. Washington, D.C.: Brassey’s, 2002. Biography of the dominant figure in mid-nineteenth century Mexican politics that examines his military and political leadership.
• Singletary, Otis A. The Mexican War. Chicago: University of Chicago Press, 1960. Concise study of the diplomacy and politics involved in the war, reviewing both the U.S. and Mexican positions. Not a detailed military history, but examines the relevance of major engagements to the final treaty.

Mexican War of Independence

Frémont Explores the American West

Mexican War

United States Occupies California and the Southwest

Taos Rebellion

Gadsden Purchase Completes the U.S.-Mexican Border

France Occupies Mexico

James Buchanan; James K. Polk; Antonio López de Santa Anna; Winfield Scott; Zachary Taylor. Guadalupe Hidalgo, Treaty of (1848)
Mexican War (1846-1848);Treaty of Guadalupe Hidalgo (1848)
Mexico;and United States[United States]
Santa Anna, Antonio López de
Bravo, Nicolás