When I first watched Beginnings, I assumed that all of the information about Wan, Raava and the time they lived in, was pretty much unknown to the world at large (since it had never been referenced before in either show).
Are Raava, Vaatu, Wan, Harmonic Convergence etc things people (or even just people like fire sages, gurus and air nomad masters) know about?
As far as I know:
- Korra's past lives mention Raava in Beginnings Part 1, but that doesn't necessarily mean anything - they are not their living selves anymore.
- The Fire Sage mentions Harmonic Convergence at the end of Beginnings Part 2, which clearly means something. But it could just be that they know that the planetary alignment is "weeks away", and know that this event has to do with something called 'Harmonic Convergence', but don't know a whole lot more than that.