When Was Mexican Cession?

The Mexican Cession (Spanish: Cesión mexicana) is the region in the modern-day southwestern United States that Mexico ceded to the U.S. in the Treaty of Guadalupe Hidalgo in 1848 after the Mexican–American War.

Why did the Mexican Cession happen?

It stemmed from the annexation of the Republic of Texas by the U.S. in 1845 and from a dispute over whether Texas ended at the Nueces River (the Mexican claim) or the Rio Grande (the U.S. claim).

How did Mexico lose California?

A border skirmish along the Rio Grande started off the fighting and was followed by a series of U.S. victories. When the dust cleared, Mexico had lost about one-third of its territory, including nearly all of present-day California, Utah, Nevada, Arizona and New Mexico.

James H. Sterling

James H. Sterling

Environmental Science & Climate Journalist

James Sterling reports on renewable energy developments, climate policy, ecological conservation, and green tech innovations around the globe.