What constitutes a definition of fascism and fascist governments has been a complicated and highly disputed subject concerning the exact nature of fascism and its core tenets debated amongst historians, political scientists, and other scholars since Benito Mussolini first used the term in 1915. Historian Ian Kershaw once wrote that "trying to define 'fascism' is like trying to nail jelly to the wall". A significant number of scholars agree that a "fascist regime" is foremost an authoritarian form of government, although not all authoritarian regimes are fascist. Authoritarianism is thus a defining characteristic, but most scholars will say that more distinguishing traits are needed to make an authoritarian regime fascist. Similarly, fascism as an ideology is also hard to define. Originally, it referred to a totalitarian political movement linked with corporatism which existed in Italy from 1922 to 1943 under the leadership of Benito Mussolini. Many scholars use the word "fascism" without capitalization in a more general sense, to refer to an ideology (or group of ideologies) which was influential in many countries at many different times. For this purpose, they have sought to identify what Roger Griffin calls a "fascist minimum"—that is, the minimum conditions that a certain political movement must meet in order to be considered "fascist". Scholars have studied the apocalyptic and millenarian aspects of fascism. By encyclopedias Encyclopaedia Britannica The Encyclopaedia Britannica defines fascism as a "political ideology and mass movement that dominated many parts of central, southern, and eastern Europe between 1919 and 1945 and that also had adherents in western Europe, the United States, South Africa, Japan, Latin America, and the Middle East.", adding that "Although fascist parties and movements differed significantly from one another, they had many characteristics in common, including extreme militaristic nationalism, contempt for electoral democracy and political and cultural liberalism, a belief in natural social hierarchy and the rule of elites, and the desire to create a (German: "people's community"), in which individual interests would be subordinated to the good of the nation." Holocaust Encyclopedia The Holocaust Encyclopedia defines fascism as "a far-right political philosophy, or theory of government, that emerged in the early twentieth century. Fascism prioritizes the nation over the individual, who exists to serve the nation." and as "an ultranationalist, authoritarian political philosophy. It combines elements of nationalism, militarism, economic self-sufficiency, and totalitarianism. It opposes communism, socialism, pluralism, individual rights and equality, and democratic government." By fascists