Benito Amilcare Andrea Mussolini (Italian pronunciation: [beˈniːto musːoˈliːni]; 29 July 1883 – 28 April 1945) was an Italian politician who led the National Fascist Party and is credited with being one of the key figures in the creation of Fascism.

Mussolini became the 40th Prime Minister of Italy in 1922 and began using the title Il Duce by 1925. After 1936, his official title was "His Excellency Benito Mussolini, Head of Government, Duce of Fascism, and Founder of the Empire". Mussolini also created and held the supreme military rank of First Marshal of the Empire along with King Victor Emmanuel III of Italy, which gave him and the King joint supreme control over the military of Italy. Mussolini remained in power until he was replaced in 1943; for a short period after this until his death, he was the leader of the Italian Social Republic.

Mussolini was among the founders of Italian Fascism, which included elements of nationalism, corporatism, national syndicalism, expansionism, social progress, and anti-socialism in combination with censorship of subversives and state propaganda. In the years following his creation of the Fascist ideology, Mussolini influenced, or achieved admiration from, a wide variety of political figures.

Among the domestic achievements of Mussolini from the years 1924–1939 were: his public works programmes such as the taming of the Pontine Marshes, the improvement of job opportunities, the public transport, and the so-called Italian economic battles. Mussolini also solved the Roman Question by concluding the Lateran Treaty between the Kingdom of Italy and the Holy See.

On 10 June 1940, Mussolini led Italy into World War II on the side of the Axis despite initially siding with France against Germany in the early 1930s. Believing the war would be short-lived, he declared war on France and the United Kingdom in order to gain territories in the peace treaty that would soon follow.

Three years later, Mussolini was deposed at the Grand Council of Fascism, prompted by the Allied invasion of Italy. Soon after his incarceration began, Mussolini was rescued from prison in the daring Gran Sasso raid by German special forces. Following his rescue, Mussolini headed the Italian Social Republic in parts of Italy that were not occupied by Allied forces.

In late April 1945, with total defeat looming, Mussolini attempted to escape to Switzerland, only to be quickly captured and summarily executed near Lake Como by Italian partisans. His body was then taken to Milan where it was hung upside down at a petrol station for public viewing and to provide confirmation of his demise.