international businessman and politically powerful head of Italy's Eni SpA (Ente Nazionale Idrocarburi; “State Hydrocarbons Authority”), which had authority over that country's oil and gas resources.

As a young man, prior to World War II, Mattei started a small chemical business in Milan, which prospered throughout his life. During the war, he worked in the underground movement and organized an anti-Fascist force 82,000 strong in northern Italy. He was decorated for these efforts and became active in the Christian Democratic Party in 1945. With his party in control of the government, Mattei was made northern commissioner of the Italian General Petroleum Agency and soon headed it. Under his leadership the agency succeeded in discovering natural gas and oil deposits in Italy, saving the country millions of lire on foreign imports.

In 1953 Italy replaced the agency with Eni and made Mattei president. Three years later, new natural resources laws were passed, limiting foreign exploration and entitling Eni to land-purchase rights around any new oil deposits. Mattei continued to expand production and Eni holdings to include gas stations, refineries, tankers, and chemical and manufacturing plants. To safeguard Italy's foreign oil supply, Mattei initiated partnerships with the governments of Egypt and Iran. Through Mattei, Eni also negotiated oil concessions in France, Africa, and Spain.