Whats Really Important?

During the novel there's lots going on, between flashback to flashback, theres war scenes and intimate scenes but in the end what really important? For me I believe that Niska's stories and flashbacks were the most important because they were the background for why Xavier killed Elijah. Elijah is the last Windigo and Xavier is the last Windigo killer, without Niska's stories we wouldn't either understand or the book would be changed completely and we wouldn't have this kind of ending at all. I feel that the war stories, although they are better than Niska's stories, are just a distraction or an intriguing plot to keep readers reading.