I wish I could get paid everytime I use "Ashbringer" in a news title. Anyway, someone was nice enough to mail me some screenshots of the Ashbringer questline in Utgarde Keep with a few explanations.
It seems that you just get the sword from an event in the dungeon, started by a guy from the Silver Hand. After that, you handle the item to a guy in Valgarde and realize that the Cleric of the Silver Hand was Tirion Fordring, he gets the sword and laugh while the retribution paladin of your party keep crying. Save the human leader, save the world.
Dialogue after you handle the sword : (Source)
A nearby cloaked Cleric walks over and reveals himself as Tirion Fordring. (model changes from the cleric to Tirion). Lord Irulon Trueblade says something about how Tirion shouldn't have revealed himself, Tirion waves him off. Dont have the exact dialogue for that, but right after it continues into this:
Highlord Tirion Fordring says: Their passing wieghs heavily upon my soul.
Lord Irulon Trueblade says: The path of freeedom has always been beset with tragedy sire. We could not risk losing you. The Order could not have survived such a blow.
Highlord Tirion Fordring says: It should have been me that carried the blade. The burden was mine to bare.
Highlord Tirion Fordring says: But you are right, Irulon. The price of our freedom will undoubtedly cost thousands more of their lives.
Highlord Tirion Fordring yells: Do you hear me Arthas? The Silver Hand comes for you! Your kingdom shall crumble beneath the weight of justice! By the light!
