Wow, thanx for the history lesson!
The Mexican War between the United States and Mexico began with a Mexican attack on American troops along the southern border of Texas on Apr. 25, 1846. Fighting ended when U.S. Gen. Winfield Scott occupied Mexico City on Sept. 14, 1847; a few months later a peace treaty was signed (Feb. 2, 1848) at Guadalupe Hidalgo. In addition to recognizing the U.S. annexation of Texas defeated Mexico ceded California and , New Mexico (including all the present-day states of the Southwest) to the United States.