Mexican-American War

1846-04-25 - 1848-02-02

The Mexican-American War (25 April 1846 to 2 February 1848) followed the 1845 U.S. annexation of Texas, which Mexico still claimed. U.S. forces invaded Mexico and occupied its capital. The war ended with the Treaty of Guadalupe Hidalgo, under which Mexico ceded roughly half its territory, including California and the Southwest, to the United States.