Reconquista

The Reconquista ("reconquest") is a term to describe an irredentist vision by different individuals, groups, and/or nations that the Southwestern United States should be politically or culturally returned to Mexico. Known as advocating a Greater Mexico, such opinions are often formed on the basis that those territories were claimed by Spain for centuries and then by Mexico from 1821 until they were ceded to the United States during the Texas Annexation (1845) and the Mexican Cession (1848) because of the Mexican–American War, however the Southwest region under Mexican ownership was sparsely populated relative to the rapid migration that occurred when the influx of Americans settled the state.