Some history for today.

The Treaty of Guadalupe Hidalgo (Tratado de Guadalupe Hidalgo in Spanish), officially titled the Treaty of Peace, Friendship, Limits and Settlement between the United States of America and the Mexican Republic, is the peace treaty signed on February 2, 1848, in the Villa de Guadalupe Hidalgo (now a neighborhood of Mexico City) between the United States and Mexico that ended the Mexican–American War (1846–1848). The treaty came into force on July 4, 1848.

With the defeat of its army and the fall of its capital, Mexico entered into negotiations to end the war. The treaty called for the U.S. to pay US$15 million to Mexico and to pay off the claims of American citizens against Mexico up to US$5 million. It gave the United States the Rio Grande as a boundary for Texas, and gave the U.S. ownership of California and a large area comprising roughly half of New Mexico, most of Arizona, Nevada, and Utah, and parts of Wyoming and Colorado. Mexicans in those annexed areas had the choice of relocating to within Mexico's new boundaries or receiving American citizenship with full civil rights.

The U.S. Senate advised and consented to ratification of the treaty by a vote of 38–14. The opponents of this treaty were led by the Whigs, who had opposed the war and rejected Manifest destiny in general, and rejected this expansion in particular. The amount of land gained by the United States from Mexico was increased as a result of the Gadsden Purchase of 1853, which ceded parts of present-day southern Arizona and New Mexico to the United States.



"Mapa de los Estados Unidos de Méjico by John Distrunell, the 1847 map used during the negotiations



Treaty of Guadalupe Hidalgo, Exchange Copy, cover. Treaty ending USA-Mexico War in 1848 and transfering large amount of territory from Mexico to USA.

TERMS

Although Mexico ceded Alta California and Santa Fe de Nuevo México, the text of the treaty[4] did not list territories to be ceded, and avoided the disputed issues that were causes of war: the validity of the 1836 secession of the Republic of Texas, Texas's unenforced boundary claims as far as the Rio Grande, and the 1845 annexation of Texas by the United States.

Instead, Article V of the treaty simply described the new U.S.–Mexico border. From east to west, the border consisted of the Rio Grande northwest from its mouth to the point Santa Fe de Nuevo Mexico (roughly 32 degrees north), as shown in the Disturnell map, then due west from this point to the 110th meridian west, then north along the 110th Meridian to the Gila River and down the river to its mouth. Unlike the New Mexico segment of the boundary, which depended partly on unknown geography, "in order to preclude all difficulty in tracing upon the ground the limit separating Upper from Lower California", a straight line was drawn from the mouth of the Gila to one marine league south of the southernmost point of the port of San Diego, slightly north of the previous Mexican provincial boundary at Playas de Rosarito.

Comparing the boundary in the Adams–Onís Treaty to the Guadalupe Hidalgo boundary, Mexico conceded about 55% of its pre-war, pre-Texas territorial claims and now has an area of 1,972,550 km² (761,606 sq mi).

In the United States, the 1.36 million km² (525,000 square miles) of the area between the Adams-Onis and Guadalupe Hidalgo boundaries outside the 1,007,935 km2 (389,166 sq mi) claimed by the Republic of Texas is known as the Mexican Cession. That is to say, the Mexican Cession is construed not to include any territory east of the Rio Grande, while the territorial claims of the Republic of Texas included no territory west of the Rio Grande. The Mexican Cession included essentially the entirety of the former Mexican territory of Alta California, but only the western portion of Santa Fe de Nuevo Mexico, and includes all of present-day California, Nevada and Utah, most of Arizona, and western portions of New Mexico, Colorado, and Wyoming.

Articles VIII and IX ensured safety of existing property rights of Mexican citizens living in the transferred territories. Despite assurances to the contrary, the property rights of Mexican citizens were often not honored by the U.S. in accordance with modifications to and interpretations of the Treaty.The U.S. also agreed to assume $3.25 million (equivalent to $91.9 million today) in debts that Mexico owed to United States citizens.

The residents had one year to choose whether they wanted American or Mexican citizenship; Over 90% chose American citizenship. The others returned to Mexico (where they received land), or in some cases in New Mexico were allowed to remain in place as Mexican citizens.

Article XII engaged the United States to pay, "In consideration of the extension acquired", 15 million dollars (equivalent to $420 million today), in annual installments of 3 million dollars.

Article XI of the treaty was important to Mexico. It provided that the United States would prevent and punish raids by Indians into Mexico, prohibited Americans from acquiring property, including livestock, taken by the Indians in those raids, and stated that the U.S. would return captives of the Indians to Mexico. Mexicans believed that the United States had encouraged and assisted the Comanche and Apache raids that had devastated northern Mexico in the years before the war. This article promised relief to them.

Article XI, however, proved unenforceable. Destructive Indian raids continued despite a heavy U.S. presence near the Mexican border. Mexico filed 366 claims with the U.S. government for damages done by Comanche and Apache raids between 1848 and 1853. In 1853, in the Treaty of Mesilla concluding the Gadsden Purchase, Article XI was annulled.

RESULTS

The land that the Treaty of Guadalupe Hidalgo brought into the United States became, between 1850 and 1912, all or part of ten states: California (1850), Nevada (1869), Utah (1896), and Arizona (1912), as well as, depending upon interpretation, the entire state of Texas (1845), which then included part of Kansas (1861); Colorado (1876); Wyoming (1890); Oklahoma (1907); and New Mexico (1912).

The remainder (the southern parts) of New Mexico and Arizona were peacefully purchased under the Gadsden Purchase, which was carried out in 1853. In this purchase the United States paid an additional $10 million (equivalent to $290 million today[when?]), for land intended to accommodate a transcontinental railroad. However, the American Civil War delayed construction of such a route, and it was not until 1881 that the Southern Pacific Railroad finally was completed, fulfilling the purpose of the acquisition.


Map o. S. Augustus Mitchell, Philadelphia, 1847. Alta California shown including Nevada, Utah, Arizona

Background to the war

Mexico had claimed the area in question since winning its independence from the Spanish Empire in 1821 following the Mexican War of Independence. The Spanish Empire had conquered part of the area from the American Indian tribes over the preceding three centuries, but there remained powerful and independent indigenous nations within that northern region of Mexico. Most of that land was too dry (low rainfall) and too mountainous to support many people, until the advent of new technology after about 1880: means for damming and distributing water from the few rivers to irrigated farmland; the telegraph; the railroad; the telephone; and electrical power.

About 80,000 Mexicans inhabited California, New Mexico, Arizona, and Texas during the period 1845 to 1850, with far fewer in Nevada, southern and western Colorado, and Utah.On 1 March 1845, U.S. President John Tyler signed legislation to authorize the United States to annex the Republic of Texas, effective on 29 December 1845. The Mexican government, which had never recognized the Republic of Texas as an independent country, had warned that annexation would be viewed as an act of war. The United Kingdom and France, both of which recognized the independence of the Republic of Texas, repeatedly tried to dissuade Mexico from declaring war against its northern neighbor. British efforts to mediate the quandary proved fruitless, in part because additional political disputes (particularly the Oregon boundary dispute) arose between Great Britain (as the ruler of Canada) and the United States.

On 10 November 1845, before the outbreak of hostilities, President James K. Polk sent his envoy, John Slidell, to Mexico. Slidell had instructions to offer Mexico around $5 million for the territory of Nuevo México and up to $40 million for Alta California. The Mexican government dismissed Slidell, refusing to even meet with him.Earlier in that year, Mexico had broken off diplomatic relations with the United States, based partly on its interpretation of the Adams–Onís Treaty of 1819, under which newly-independent Mexico claimed it had inherited rights. In that agreement, the United States had "renounced forever" all claims to Spanish territory.

Neither side took any further action to avoid a war. Meanwhile, Polk settled a major territorial dispute with Britain via the Oregon Treaty, which was signed on 15 June 1846. By avoiding any chance of conflict with Great Britain, the U.S was given a free hand in regard to Mexico. After the Thornton Affair of 25–26 April, when Mexican forces attacked an American unit in the disputed area, with the result that 11 Americans were killed, five wounded and 49 captured, Congress passed declaration of war, which Polk signed on 13 May 1846. The Mexican Congress responded with its own war declaration on 7 July 1846

More

The fact we paid them $15 million -- several billion in today's dollars -- for land that was largely uninhabited and considered to be worthless desert is never brought up when Lefties talk about how we "stole" Mexico's land in the War with Mexico.

Nicolas Trist my man!

Not to mention Mexico did not have the resources to adequately (or willingness) to commit troops to their northern regions to protect settlements, missionaries and ranches from hostile indians.

How did that go again with the US stealing those lands? Then the Gadsen Purchase a few years later?

Article states $420M for the big chunk. About 250 for the rest over the years

Interesting that we were so gracious in victory. I had no idea that some of the terms listed were even issues, granted this is all but a forgotten war for us.

It wasn't that much taking inflation into account.  Hundreds of millions, IIRC.

Of course, we still forced them to cede the territory even though we were willing to give them some money for it.  What they seem to ignore or find a way to reject is the fact that the Mexicans made a military incurision into one of the United States and killed, wounded, and captured Federal soldiers.  The fact that they represented a strategic threat to the U.S. in the long run was also evident at the time (war was probably inevitable in that context).  They gave us plenty of causus belli.  They started it; we ended it, and did so in the end through a daring and brilliant campaign by General Scott (probably one of the greatest U.S. generals in history) which was praised throughout the Western world.  The war ending in annexation was justified, and the land earned through the incredible efforts of our military and their blood, nto to mention the monies paid.

This was negotiated by a relative, Ambrose Hundley Sevier.

ETA first cousin five times removed

We should have kept everything above the Tropic of Cancer.

We should have took more land.

We should have taken Northern Mexico and pushed them Southward.........................