Official Mexican government holiday, celebrated annually in Mexico on November 20, marking the start of what became the Mexican Revolution. The Mexican Revolution brought the overthrow of liberal Army general Porfirio Díaz after 35 years as president of Mexico. In the 1910 presidential election, wealthy landowner Francisco I. Madero opposed Díaz. Díaz jailed Madero, who then escaped, issuing the Plan of San Luis Potosí on October 6, 1910. In the plan, Madero, declared the results of the 1910 election fraudulent, nullified them, asserted that he was provisional president, and called for Mexicans to rise up against Díaz on November 20, 1910.