History, much like science, is not “truth”, but instead truth through people’s eyes. A war was ended, but why did it end? Who won? Why did the victors win? Were they honorable? Will this war even be remembered? These questions are answered differently depending on the historian’s bias and perspective.
The same should be said for fantasy histories.
While it’s true that you, the writer, know “everything there is to know” about this world, it doesn’t mean anyone else does. In fact, I believe this simply should not be the case. World building is by nature a mirage, a simulation of a real world: you may know that it has issues, holes, and so on, but one must never reveal these secrets, for doing so can destroy the immersion your world is trying to achieve. Adding uncertainty to the historic events and writings adds another level of immersion, and another layer of depth that makes the world feel more real, as well as hiding any holes in a logical way – if the ogres have never traveled to the edge of the world, then there is no need to explain why you haven’t developed the edge of the world, and so on. (Although it’s always a good idea to somewhat develop important areas that no one else knows about!)
This also gives a bit of leeway to make mistakes, since often inconsistencies spring up on their own… these of course must be kept to a minimum, but it’s a nice perk.
And of course, this strategy is realistic. People don’t agree, they carry biases and lack of knowledge that leads them to make assumptions and claims that end up being quickly accepted by anyone sharing said biases. This can end up as “common knowledge”, while the truth is lost, forever.
However, this inconsistency must remain consistent – otherwise the mirage will crumble, feeling like a confusing mess. There is a balance to everything.
For Ardenfall specifically, I hope to maintain this balance of consistent inconsistency – sharing the knowledge of the world through dialog and books, while also making it clear that none of these books or dialog are “truths”, simply the truth through the peoples eyes.