A dictatorship is a form of government which is characterized by a leader who holds absolute or near-absolute political power. Politics in a dictatorship are controlled by a dictator, and they are facilitated through an inner circle of elites that includes advisers, generals, and other high-ranking officials. The dictator maintains control by influencing and appeasing the inner circle and repressing any opposition, which may include rival political parties, armed resistance, or disloyal members of the dictator's inner circle. Dictatorships can be formed by a military coup that overthrows the previous government through force or they can be formed by a self-coup in which elected leaders make their rule permanent. Dictatorships are authoritarian or totalitarian, and they can be classified as military dictatorships, one-party dictatorships, and personalist dictatorships.

The Latin word dictator originated in the early Roman Republic to refer to a constitutional office with "a temporary grant of absolute power to a leader to handle some emergency." Modern dictatorships first developed in the 19th century, which included Bonapartism in Europe and caudillos in Latin America. With the advent of the 19th and 20th centuries, dictatorships and constitutional democracies emerged as the world's two major forms of government, gradually eliminating monarchies, one of the traditional widespread forms of government of the time. Typically, common aspect that characterized dictatorship is suppressing freedom of thought and speech of the masses, in order to maintain complete political and social supremacy and stability. Dictatorships generally employ political propaganda to decrease the influence of proponents of alternative governing systems. The 20th century saw the rise of fascist and communist dictatorships in Europe; fascism was largely eradicated in the aftermath of World War II in 1945, while communism spread to other continents, maintaining prominence until the end of the Cold War in 1991.