Mexican Revolution revolution was in 1914, during the "Ypiranga" incident. When United States intelligence agents received word that the "Ypiranga", a German merchant ship, contained illegal firepower for Huerta, President Wilson ordered American troops to the port of Veracruz to stop the ship from docking. Wilson never actually declared war on Mexico. The United States skirmished with Huerta's troops in Veracruz. The "Ypiranga" successfully docked at another port and unloaded the arms, which greatly angered Wilson. The ABC Powers arbitrated and U.S. troops left Mexican soil, but the incident added to already tense Mexican-American relations. In 1916, in retaliation for Pancho Villa's
History of the Mexican Americans in Los Angeles los Ángeles", was constructed in its place a mere thirty years later. The city has witnessed a development of a Hispanic (mainly Mexican) cultural presence since its settlement as a city in 1769. Mexican-Americans have been one of the largest ethnic groups in Los Angeles since the 1910 census, as Mexican immigrants and US-born Mexicans from the Southwest states came to the booming industrial economy of the LA area between 1915 and 1960. This migration peaked in the 1920s and again in the World War II era (1941–45). The city's original barrios were located in the eastern half of the