Reading a bit about Marxism (from second hand sources) and it is saying in any society A will happen then B will happen and so on.
So was Marx a futurist much like Asimov. Asimov wrote a lot about robots and his three laws. And now, people are building robots and thinking about how to implement his three laws. They could be called Asimovists, to coin a phrase.
Another person who did something similar was Nostrodamus, who made many predictions about the future.
And then there were the old testament prophets such as Isaiah. Some might say Jesus made those into self-fulfilling prophesies by letting other assign him the label of Messiah.
It is not unheard of for a science fiction writer to later be revered for his ideologies (e.g. L Ron Hubbard).
Another one of those self fulfilling prophecies might be the idea that the lost tribes of Israel coming back together will be associated with the coming of the new Messiah. And then the attempt to fulfill this prophecy.
So what category would you put Marxism in? Political theory, futurism, science fiction, soothsaying, prophecy or something else?