The Mexican–American War, also known in the United States as the Mexican War and in Mexico as the Intervención estadounidense en México (United States intervention in Mexico), was an armed conflict between the United States and Mexico from 1846 to 1848. It followed the 1845 American annexation of Texas, which Mexico still considered its territory. Mexico refused to recognize the Velasco treaty, because it was signed by President Antonio López de Santa Anna while he was captured by the Texan Army during the 1836 Texas Revolution. The Republic of Texas was de facto an independent country, but most of its Anglo-American citizens wanted to be annexed by the United States.