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Drawing the Line

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Bordering the Future

The Treaty of Guadalupe Hidalgo, ending the Mexican War, was signed on February 2, 1848, by Nicholas P. Trist for the U.S. and by a special commission representing the collapsed government of Mexico. Under the treaty, Mexico ceded to the U.S. upper California and New Mexico, including Arizona, and recognized U.S. claims over Texas, with the Rio Grande as its southern boundary. In the Treaty of Guadalupe Hidalgo, signed that February day, Mexico gave up its claim to Texas as well as an area now in the states of New Mexico, Utah, Nevada, Arizona, California, and western Colorado. The U.S., in turn, paid Mexico $15 million and assumed the claims of U.S. citizens against Mexico, recognized prior land grants in the Southwest, and offered citizenship to any Mexicans residing in the area. Article V of the treaty states:

The boundary line between the two Republics shall commence in the Gulf of Mexico, three leagues from land, opposite the mouth of the Rio Grande, otherwise called Río Bravo del Norte, or (o)pposite the mouth of its deepest branch, if it should have more than one branch emptying directly into the sea; from thence up the middle of that river, following the deepest channel, where it has more than one, to the point where it strikes the southern boundary of New Mexico; thence, westwardly, along the whole southern boundary of New Mexico (which runs north of the town called Paso) to its western termination; thence, northward, along the western line of New Mexico, until it intersects the first branch of the river Gila; (or if it should not intersect any branch of that river, then to the point on the said line nearest to such branch, and thence in a direct line to the same); thence down the middle of the said branch and of the said river, until it empties into the Rio Colorado; thence across the Rio Colorado, following the division line between Upper and Lower California, to the Pacific Ocean.1

To avoid boundary disputes, negotiators stipulated that surveyors from Mexico and the U.S. would jointly mark off the new dividing line within a year by traversing the border from San Diego on the Pacific Ocean to the mouth of the Rio Grande. "They shall keep journals and make out plans of their operations; and the result agreed upon by them shall be deemed a part of this treaty, and shall have the same force as if it were inserted therein," the treaty states.

"The boundary line established by this article shall be religiously respected by each of the two republics, and no change shall ever be made therein, except by the express and free consent of both nations, lawfully given by the General Government of each, in conformity with its own constitution."

ENDNOTES

1 Treaty of Guadalupe Hidalgo, (http://www.monterey.edu/other-sites/history/treaty.html). (Internet document.)

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