The 'fairy-like' sami people from northern finland and norway are not quite as described in reality, though the fashion is pretty much on point. And things like hunting, war, and other gritty realities of the era are somewhat romanticized - as if aiming for a pg rating
With all of his intelligence and knowledge of future events, It feels like he should be better able to control the course of events without relying so much on others' cooperation.
It's enjoyable how much his past life affects his decisions and choices. It really makes the character feel complete (though morbidly insane). And MC really does manage to be charming despite his evil-ness, making you constantly second-guess whether you fully understand him.