The Treaty of Guadalupe Hidalgo is the peace agreement signed on 2 February 1848 between the United States and Mexico that formally ended the Mexican-American War (1846-1848). Under its terms, Mexico ceded to the United States a vast territory encompassing present-day California, Nevada, Utah, Arizona, New Mexico, Colorado, and Wyoming in exchange for a payment of $15 million and the assumption of certain claims held by American citizens against the Mexican government. The treaty also established the Rio Grande as the southern boundary of Texas. Its significance-legal, moral, and geopolitical-remains a subject of ongoing scholarly and public debate.

The treaty was negotiated in the village of Guadalupe Hidalgo, north of Mexico City, while American forces occupied the Mexican capital. Nicholas Trist, a State Department envoy, conducted negotiations on behalf of the United States. The Senate ratified the treaty on 10 March 1848, with modifications. For extended historical background, see treaty-of-guadalupe-hidalgo-history.

Scholars have thoroughly documented the treaty's provisions and immediate consequences. Mexico surrendered approximately 525,000 square miles-roughly half its national territory at the time-and approximately 80,000 to 100,000 Mexican nationals living in the ceded region became eligible for American citizenship under Article VIII. Article IX (as modified by the Senate) and Article X (which the Senate struck entirely) concerned the political rights and land grants of existing residents; the deletion of Article X and its guarantees of prior Mexican land grants has generated sustained legal and historical debate. Contemporary research continues to examine the treaty's implementation, the subsequent dispossession of Californio and Nuevomexicano landholders, and the treaty's status in present-day land and water rights litigation.

American expansionist fulfillment: Some historians and commentators frame the treaty as a legitimate conclusion to a war fought in defense of Texas annexation and the principle of Manifest Destiny, yielding territory whose development served broader hemispheric interests. See treaty-of-guadalupe-hidalgo-american-expansionist-viewpoint.

Mexican national loss and violation: A substantial body of Mexican and Chicano/a scholarship characterizes the treaty as the product of an unjust war of aggression that stripped Mexico of a major portion of its territory and left its former citizens vulnerable to systematic dispossession. See treaty-of-guadalupe-hidalgo-mexican-national-loss-viewpoint.

Protections unfulfilled: Legal scholars and advocates argue that the treaty's guarantees to existing residents-particularly land grants, language rights, and civil protections-were systematically undermined by subsequent American legislation and court decisions, constituting a continuing legal and moral obligation. See treaty-of-guadalupe-hidalgo-unfulfilled-protections-viewpoint.

Foundational document of Chicano identity: Within Chicano/a and Latino studies, the treaty is read as a constitutive event that created a subordinated population within the United States and forms the basis of ongoing claims to cultural presence and political rights in the Southwest. See treaty-of-guadalupe-hidalgo-chicano-identity-viewpoint.

Deletion of Article X: The Senate's removal of Article X, which would have honored prior Mexican land grants, has been the subject of sustained legal challenges and historical criticism regarding federal obligation to former Mexican landholders. See treaty-of-guadalupe-hidalgo-article-x-deletion-controversy.

Trist's unauthorized negotiation: Nicholas Trist concluded negotiations after being officially recalled, raising constitutional and diplomatic questions about the treaty's procedural legitimacy that were debated at the time and revisited by later scholars. See treaty-of-guadalupe-hidalgo-trist-unauthorized-negotiation-controversy.

Citizenship and racial eligibility: Because Article VIII conditioned citizenship on racial eligibility requirements then operative in American law, Mexican nationals of Indigenous or African descent faced contested and often denied citizenship claims; this exclusion has been documented and debated in legal history. See treaty-of-guadalupe-hidalgo-citizenship-racial-eligibility-controversy.

• treaty-of-guadalupe-hidalgo-history - History
• Mexican-American War - Main Topic
• treaty-of-guadalupe-hidalgo-article-x-deletion-controversy - Controversy
• treaty-of-guadalupe-hidalgo-trist-unauthorized-negotiation-controversy - Controversy
• treaty-of-guadalupe-hidalgo-citizenship-racial-eligibility-controversy - Controversy
• treaty-of-guadalupe-hidalgo-american-expansionist-viewpoint - Viewpoint
• treaty-of-guadalupe-hidalgo-mexican-national-loss-viewpoint - Viewpoint
• treaty-of-guadalupe-hidalgo-unfulfilled-protections-viewpoint - Viewpoint
• treaty-of-guadalupe-hidalgo-chicano-identity-viewpoint - Viewpoint
• manifest-destiny - Main Topic
• united-states-mexico-border - Main Topic
• california-statehood - Main Topic
• nuevomexicano-land-grants - Main Topic

1. Richard Griswold del Castillo, The Treaty of Guadalupe Hidalgo: A Legacy of Conflict (Norman: University of Oklahoma Press, 1990). 2. David M. Pletcher, The Diplomacy of Annexation: Texas, Oregon, and the Mexican War (Columbia: University of Missouri Press, 1973). 3. Treaty of Guadalupe Hidalgo, 9 Stat. 922 (1848), signed 2 February 1848, ratified by the United States Senate 10 March 1848. 4. Timothy J. Henderson, A Glorious Defeat: Mexico and Its War with the United States (New York: Hill and Wang, 2007). 5. Paul Foos, A Short, Offhand, Killing Affair: Soldiers and Social Conflict during the Mexican-American War (Chapel Hill: University of North Carolina Press, 2002). 6. Arnoldo De León, They Called Them Greasers: Anglo Attitudes toward Mexicans in Texas, 1821-1900 (Austin: University of Texas Press, 1983). 7. Laura E. Gómez, Manifest Destinies: The Making of the Mexican American Race (New York: New York University Press, 2007).