But for the region's Mexicans, the war's consequences were monumentally disastrous. When the treaty ending the war was signed, there were perhaps eighty thousand Mexican residents in the former Mexican territories that became the Southwestern United States. In the years that followed the war they suffered a massive loss of land and political influence.
In early 1848, following the United States capture and occupation of Mexico City, negotiations drew up a preliminary draft of the treaty. After revision by the Senate, the Treaty of Guadalupe Hidalgo, signed in the Villa de Guadalupe across from the shrine dedicateed to Mexico's patron saint, the Virgin of Guadalupe, was ratified by both governments later that year. In return for the northern third of Mexico, the United States agreed to pay $15 million and to assume up to $3.25 million in claims by its citizens against the Mexican government. The treaty guaranteeded Mexicans newly absorbed into the United States and to their descendants certain political rights, including land rights.
In 1853, the United States purchased a thirty thousand square mile strip of land in southern Arizona and New Mexico for $10 million. Acquired for a southern transcontinental railroad route, the Gadsden Purchase had profound consequences for the Mexicans who resided in the region. Two thousand Mexicans from the conquered lands who had moved to northern Mexico suddenly found themselves annexed by the United States.
The Treaty of Guadalupe Hidalgo gave Mexicans the right to remain in United States territory or to move to Mexico. About three thousand chose to