A war between the U.S. and Mexico spanned the period from spring 1846 to fall 1847. The war was initiated by the United States and resulted in Mexico's defeat and the loss of approximately half of its national territory in the north. In the U.S. the war is termed the Mexican–American War, also known as the Mexican War, the U.S.–Mexican War or the Invasion of Mexico. In Mexico names for the war include Primera intervención estadounidense en México (United States' First Intervention in Mexico), Invasión estadounidense a México ("United States' Invasion of Mexico"), Guerra de la Invasión estadounidense, and Guerra del 47 ("The War of 1847").