Mexican oil expropriation

The Mexican oil expropriation (Spanish: expropiación petrolera en México) was the nationalization of all petroleum reserves, facilities, and foreign oil companies in Mexico on March 18, 1938. In accordance with Article 27 of the Constitution of 1917, President Lázaro Cárdenas declared that all mineral and oil reserves found within Mexico belong to the nation. The Mexican government established a state-owned petroleum company, Petróleos Mexicanos, or PEMEX.

For a short period, this measure caused an international boycott of Mexican products in the following years, especially by the United States, the United Kingdom, and the Netherlands, as well as large foreign oil companies who had expertise refining Mexican oil. However, with the outbreak of World War II and the alliance between Mexico and the Allies, the disputes with private companies over compensation were resolved.