Final answer:
Mexico was forced to give a large portion of its territory to the United States as a result of the Mexican-American War, known as the Gadsden Purchase.
Step-by-step explanation:
As a result of the Mexican-American War, Mexico was forced to give a large portion of its territory to the United States. This agreement was known as the Gadsden Purchase, which took place in 1853. The United States acquired a strip of land in present-day southern Arizona and southern New Mexico as a result.
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