What part of the US was Mexico?
Ava Arnold
Updated on February 19, 2026
Mexican land was eventually divided into all or part of Colorado, New Mexico, California, Arizona, Nevada, Utah, and Wyoming. Nearly 80,000 Mexican citizens lived in this area, and the Treaty of Guadalupe Hidalgo promised to protect them.
How did Mexico lost its land to the US?
Treaty of Guadalupe Hidalgo: February 2, 1848The treaty added an additional 525,000 square miles to United States territory, including the land that makes up all or parts of present-day Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming.