The nationalization of oil supplies refers to the process of confiscation of oil production operations and their property, generally for the purpose of obtaining more revenue from oil for the governments of oil-producing countries.

The nationalization of the Iranian oil industry resulted from a movement in the Iranian parliament (Majlis) to seize control of Iran's oil industry, which had been run by private companies, largely controlled by foreign interests.

The so-called nationalization campaign, was the set of measures taken by the Brazilian government during the Estado Novo of Getúlio Vargas to reduce the influence of foreign immigrant communities in the country and force their integration with the Brazilian population.