Adolf Hitler Allegory
Adenoid Hynkel is an allegory of Adolf Hitler, sharing both the same initials and the real life dictator's determination to carry out the extermination of the Jews. Like Hitler, he is a narcissistic empire builder, invading and occupying neighboring countries. He is also shown as not being particularly intelligent, relying on his secretaries and generals to develop his policies of hate. Originally the movie was not going to be shown in the UK because of the government's policy of appeasement when it came to Germany, but by the time it was released, Britain and Germany were at war, and so a film that portrayed a clearly Hitler-like character on the screen was incredibly popular.
Holocaust Allegory
The Barber and Hannah live in the ghetto area of the city, because they are Jewish. They are under constant threat from the policies of Garbitch and Herring, the creators of the plan to exterminate the Jews. Jews were therefore arrested and taken to concentration camps, just like the Jewish holocaust victims the movie allegorizes.
Napaloni Allegory
Napaloni is an allegory of Benito Mussolini, Italian dictator and willing participant in Hitler's plan for Europe and the world. He plays second fiddle to Hynkel, but is a partner in his fascism.
Herring
Herring is not just an allegory; he is an obvious pun, given that his name is an amalgamation of the name of the man he is allegorizing - Hermann Gorring. Gorring was Hitler's "second in command" in working the Nazi machine, masterminding the propaganda in particular, in the same way that Herring is a loyal underling to Hynkel.
Garbitsch Allegory
Garbitsch is an allegory of Adolf Eichmann, the evil mind behind the "final solution" and the extermination of the Jews; Garbitsch is the mind behind Hynkel's plan to do the same.
