Mexico's refusal to recognize the independence of Texas was a major factor in the outbreak of the Mexican-American War. Mexico viewed the annexation of Texas by the United States as an act of aggression and a violation of the 1836 Treaty of Velasco, which had ended the Texas Revolution. Mexico's refusal to recognize the independence of Texas and its subsequent annexation by the United States led to a breakdown in diplomatic relations between the two countries and ultimately to the outbreak of war.
