I've not seen this Charlie Chaplin classic since highschool- but does his satirical depiction of Adenoid Hynkel & his Jewish barber double- together with his incongruously making a speech for world peace- constitue a form of AH ?
"Sir, the workers are complaining about the sawdust in the bread."The Great Dictator is more satire than anything else. It isn't trying to create an alternate world, simply to poke fun at the Hitler regime.
Also, I do recommend watching it. It might not be AH, but it is still a damn good film.