Plutarco Elías Calles (born Francisco Plutarco Elías Campuzano; 25 September 1877 – 19 October 1945) was a Mexican politician and military officer who served as the 47th President of Mexico from 1924 to 1928. After the assassination of Álvaro Obregón, Calles founded the Institutional Revolutionary Party and held unofficial power as Mexico's de facto leader from 1929 to 1934, a period known as the Maximato. Previously, he served as a general in the Constitutional Army, as Governor of Sonora, Secretary of War, and Secretary of the Interior. During the Maximato, he served as Secretariat of Public Education, Secretary of War again, and Secretary of the Economy. During his presidency, he implemented many left-wing populist and secularist reforms, opposition to which sparked the Cristero War.
Born on 25 September 1877 in Sonora, Calles fought in Venustiano Carranza's Constitutional Army during the Mexican Revolution, which allowed him to rise in politics, joining the cabinets of Presidents Carranza, Adolfo de la Huerta, and Álvaro Obregón. Obregón selected him as the Laborist Party's candidate in the 1924 election. His campaign was the first populist presidential campaign in Mexico's history, as he called for land redistribution and promised equal justice, further labor rights, and democratic governance. He won the election and expanded education, implemented infrastructure projects, and improved public health. After this populist phase (1924–1926) he began to persecute the Catholic Church in Mexico (1926–1928), passing several anticlerical laws that resulted in the Cristero War. He allowed CROM's Luis N. Morones to consolidate unions under the Laborist Party, and launched a failed attempt to cancel the Bucareli Treaty. Obregón still held significant political sway and was Calles's main base of support.
