Adolfo López Mateos (; 26 May 1910 – 22 September 1969) was a Mexican politician affiliated with the Institutional Revolutionary Party (PRI) who served as President of Mexico from 1958 to 1964. As president, he nationalized electric companies, created the National Commission for Free Textbooks (1959) and promoted the creation of prominent museums such as the Museum of Natural History and the National Museum of Anthropology in Mexico City. Declaring his political philosophy to be "left within the Constitution," López Mateos was the first left-wing politician to hold the presidency since Lázaro Cárdenas.