Lázaro Cárdenas del Río (May 21, 1895 – October 19, 1970) was President of Mexico from 1934 to 1940.

Lázaro Cárdenas was born into a lower-middle class family in the village of Jiquilpan, Michoacán. He supported his family (including his mother and 7 younger siblings) from age 16 on after the death of his father. By the age of 18 he had worked as a tax collector, a printer's devil, and a jailkeeper. Although he left school at the age of eleven, he used every opportunity to educate himself and read widely throughout his life, especially works of history.

Cárdenas originally set his sights at becoming a teacher, but was drawn into politics and the military during the Mexican Revolution after Victoriano Huerta overthrew President Francisco Madero. He backed Plutarco Elías Calles, and after Calles became President, Cárdenas became governor of Michoacán in 1928. He became known for his progressive program of building roads and schools, promoting education, and land reform, as well as the unusually strict honesty of his administration.

Calles continued to dominate Mexico after his presidency with administrations that were his puppets. He selected Cárdenas to be the PRI's presidential candidate on the assumption that he could control Cárdenas as he had controlled others. Cárdenas's first move once he took office late in 1934 was to have his presidential salary cut in half. Even more surprising moves would follow. After establishing himself in the presidency, Cárdenas had Calles and dozens of his corrupt associates arrested or deported to the United States, a decision that was greeted with great enthusiasm by the majority of the Mexican public.

Cárdenas is considered by many historians to be the creator of a political system that lasted in Mexico until the end of the 1980s. At its heart were nationalistic policies involving Mexico's vast oil production, which had soared following strikes in 1910 in the area known as the "Golden Lane," near Tampico, and which made Mexico the world's second-largest oil producer by 1921, supplying approximately 20 percent of domestic demand in the United States.

Cárdenas's efforts to negotiate with Mexican Eagle, in the managerial control of Royal Dutch/Shell, and Standard Oil of New Jersey were unavailing, and the companies rejected a solution proposed by a presidential commission. So at 9:45 p.m. on the evening of March 18, 1938, Cárdenas nationalized Mexico's petroleum reserves and expropriated the equipment of the foreign oil companies in Mexico. The announcement inspired a spontaneous six-hour parade in Mexico City.

Even though compensation for the expropriated assests was included in this legislation, the act angered the international business community and vexed foreign governments, especially Great Britain. The British severed diplomatic relations with Cárdenas's government, and Mexican oil and other goods were boycotted. However, with the outbreak of World War II, oil became a highly sought-after commodity and the boycott ended. The Mexican company that Cárdenas founded, Petróleos Mexicanos (or Pemex), would later be a model for other nations seeking greater control over their own oil and natural gas resources.

After his presidential term, Cárdenas served as Mexico's secretary of defense through 1945.

It is often said that Lázaro Cárdenas was the only president from the PRI who did not use the office to make himself wealthy. He retired to a modest home by Lake Pátzcuaro and worked the rest of his life supervising irrigation projects and promoting free medical clinics and education for the nation's poor.

Lázaro Cárdenas died of cancer in Mexico City. His son Cuauhtémoc Cárdenas is a prominent Mexican politician.

In his honor, quite a few cities in Mexico have named streets after him, including highways in Guadalajara and Monterrey.

See also: History of Mexico