One of the more interesting interpretations of Frankenstein is as a metaphor for the working class, one created by the bourgeoisie (in the form of Victor Frankenstein) which then tried to kill him. There are a couple of interesting essays about this available online—I like this one by Luisa Umana.
[T]he monster is a symbol for oppressed people. He is the proletariat that revolts against the bourgeoisie in class struggle. … [H]his very composition is symbolic of the laborers who were composed of many different types of people, larger in numbers, physically stronger, and less dependent on luxury than the upper classes.I don’t think that there is much of a historical case Shelley writing with this metaphor in mind. Yet, as perhaps the foundational text of the sci-fi genre, Frankenstein’s framing of collectives as terrifying and monstrous (e.g., the Borg, Cylons, the bugs in Starship Troopers) may help explain the near absence of positive representations of collectives (e.g., trade unions) in the genre.
-- Bob Barnetson