Early concepts and use
The notion of totalitarianism as a "total" political power by the state was formulated in 1923 by Giovanni Amendola, who described Italian Fascism as a system fundamentally different from conventional dictatorships. The term was later assigned a positive meaning in the writings of Giovanni Gentile, Italy’s most prominent philosopher and leading theorist of fascism. He used the term totalitario to refer to the structure and goals of the new state, which were to provide the "total representation of the nation and total guidance of national goals". He described totalitarianism as a society in which the ideology of the state had influence, if not power, over most of its citizens. According to Benito Mussolini, this system politicizes everything spiritual and human: "Everything within the state, nothing outside the state, nothing against the state". 
One of the first to use the term "totalitarianism" in the English language was the Austrian writer Franz Borkenau in his 1938 book The Communist International, in which he commented that it united the Soviet and German dictatorships more than it divided them. The label "totalitarian" was twice affixed to the Hitler regime during Winston Churchill's speech of October 5, 1938 before the House of Commons in opposition to the Munich Agreement, by which France and Great Britain consented to Nazi Germany's annexation of the Sudetenland. Churchill was then a backbencher MP representing the Epping constituency. In a radio address two weeks later, Churchill again employed the term, this time applying the concept to "a Communist or a Nazi tyranny".
The leader of the historic Spanish reactionary conservative party called the Spanish Confederation of the Autonomous Right declared his intention to "give Spain a true unity, a new spirit, a totalitarian polity" and went on to say: "Democracy is not an end but a means to the conquest of the new state. When the time comes, either parliament submits or we will eliminate it".
George Orwell made frequent use of the word totalitarian and its cognates in multiple essays published in 1940, 1941 and 1942. In his essay Why I Write, he wrote: "The Spanish war and other events in 1936-37 turned the scale and thereafter I knew where I stood. Every line of serious work that I have written since 1936 has been written, directly or indirectly, against totalitarianism and for democratic socialism, as I understand it".
During a 1945 lecture series entitled The Soviet Impact on the Western World (published as a book in 1946), the pro-Soviet British historian E. H. Carr claimed: "The trend away from individualism and towards totalitarianism is everywhere unmistakable" and that Marxism–Leninism was by far the most successful type of totalitarianism as proved by Soviet industrial growth and the Red Army's role in defeating Germany. Only the "blind and incurable" could ignore the trend towards totalitarianism, said Carr.
In The Open Society and Its Enemies (1945) and The Poverty of Historicism (1961), Karl Popper articulated an influential critique of totalitarianism: in both works, he contrasted the "open society" of liberal democracy with totalitarianism and argued that the latter is grounded in the belief that history moves toward an immutable future in accordance with knowable laws.
In The Origins of Totalitarianism, Hannah Arendt argued that Nazi and Communist regimes were new forms of government and not merely updated versions of the old tyrannies. According to Arendt, the source of the mass appeal of totalitarian regimes is their ideology, which provides a comforting, single answer to the mysteries of the past, present and future. For Nazism, all history is the history of race struggle and for Marxism all history is the history of class struggle. Once that premise is accepted, all actions of the state can be justified by appeal to nature or the law of history, justifying their establishment of authoritarian state apparatus.
In addition to Arendt, many scholars from a variety of academic backgrounds and ideological positions have closely examined totalitarianism. Among the most noted commentators on totalitarianism are Raymond Aron, Lawrence Aronsen, Franz Borkenau, Karl Dietrich Bracher, Zbigniew Brzezinski, Robert Conquest, Carl Joachim Friedrich, Eckhard Jesse, Leopold Labedz, Walter Laqueur, Claude Lefort, Juan Linz, Richard Löwenthal, Karl Popper, Richard Pipes, Leonard Schapiro and Adam Ulam. Each one of these describes totalitarianism in slightly different ways, but they all agree that totalitarianism seeks to mobilize entire populations in support of an official state ideology and is intolerant of activities which are not directed towards the goals of the state, entailing repression or state control of business, labour unions, non-profit organizations, religious organizations and buildings and political parties.