All Mexicans know that before the 1846–48 war with the United States the land that is now Texas, California, New Mexico, and Arizona was part of Mexico. The conflict led to half of Mexico’s territory being ceded to the United States. However, there is no serious political movement to regain the region and no pressing border dispute between the two countries. Throughout most of the twentieth century they squabbled over a small piece of land after the Rio Grande changed course in the 1850s, but in 1967 both sides agreed the area was legally part of Mexico.
