Lázaro Cárdenas del Río was a Mexican soldier and politician. He was a general in the Constitutionalist Army during the Mexican Revolution and a statesman who served as President of Mexico between 1934 and 1940. He is best known for nationalization of the oil industry in 1938 and the creation of Pemex, the government oil company. He also revived agrarian reform in Mexico, expropriating large landed estates and redistributing land to smallholders in collective holdings.
Although he was not from the state of Sonora, whose generals had dominated Mexican politics in the 1920s, Cárdenas was loyal to Sonoran general and former president Plutarco Elías Calles. Calles had founded the National Revolutionary Party in the wake of the assassination of Sonoran general Alvaro Obregón, who served as president and was president-elect in 1928. Cárdenas was Calles' hand-picked candidate in 1934 to run for the presidency. While Calles did not hold the title of president, he had remained the power behind the presidency, and expected to maintain that role when Cárdenas took office.