Encyclopedia of the Great Plains

GUADALUPE HIDALGO, TREATY OF

Signed on February 2, 1848, the Treaty of Guadalupe Hidalgo officially ended the Mexican American War (1846-48). The treaty required that Mexico cede 947,570 square miles, almost half of its territory, in exchange for peace and $15 million. The United States gained most of what is now the American Southwest and parts of the Great Plains, including New Mexico, Arizona, Utah, Nevada, California, and parts of Wyoming, Colorado, and Oklahoma. The treaty also recognized the annexation of Texas to the United States and set the boundary between the two nations at the Rio Grande.

Key factors leading to the war, as well as the eventual terms of the treaty, included the annexation of Texas by the United States, an almost religious belief in American manifest destiny, and a vulnerable Mexican government. Unfortunately for Mexico, a succession of overthrown presidents had followed its war of independence from Spain, leaving the unstable nation an easy target for American expansionism.

Appointed by President James Polk, Nicholas Trist traveled to Mexico in May 1847 and began diplomatic relations soon after. He and three Mexican peace commissioners eventually signed the treaty at Villa de Guadalupe Hidalgo, but ratification would be an arduous process for both countries. While Mexican o.cials were outraged about lost territory, Americans were equally disappointed that they would not receive even more of the defeated nation.

Aside from land and money, the treaty dealt with the citizenship and property rights of those living within the transferred territory: Mexican citizens could relocate to Mexico, remain in the territory as Mexican citizens, or become citizens of the United States. The treaty promised these new Americans all rights, including "free enjoyment of liberty and property." The ratification did not, however, include Article 10 of the original document, which had promised to honor Mexican land grants.

Mary E. Adams University of Oklahoma

del Castillo, Richard Griswold. The Treaty of Guadalupe Hidalgo: A Legacy of Conflict. Norman: University of Oklahoma Press, 1990.

Gonzales, Manuel G. Mexicanos: A History of Mexicans in the United States. Bloomington: Indiana University Press, 1999.