Well the fact that this is how things are happening is hardly common knowledge, it's really just the actions of a single person, the last known remaining member of the party of Heroes that took down and sealed away Evil in the first place hundreds of years ago which turned the tide of the war (He's an elf which are long lived which is why he's basically the only one still around*) and is now basically the de facto ruler of things. The... 'Big Good' as it were. Most of the rest of the world doesn't really concern themselves with just
how the world as a whole has been in a state of peace and goodness and if I remember correctly not even the people who work for the elf guy really seem aware of just hat he's been doing other then that they seek out 'troublemakers' and he 'takes care of them'. I mean, taking things away from the prospective of the protagonists and to the 'good guy's' side of things, this legendary hero comes to you and says that this ragtag group of ne'erdowells are trying to bring Evil back into the world, that alone sounds like a working plot to any number of fantasy novels (which is the point), it would take a
very questioning mind to say 'Well, how do we know that that's a bad thing?'
It's also probably important to know that it's not like he just did this all at once but rather has been doing it slowly over a hundred years or so...
Spoiler: *
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Spoiler: No really
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The fact that he isn't is probably my favorite twist in the book and I'm torn at if I should really say anything further on it, if even just saying that might be giving to much away.