>>542634375
A dreary tale. Bardin, once an ironbreaker for his hold defending the deep depths. His outpost was ambushed by skaven. The lone survivor and heavily injured he was unable to sound the warning of the impending skaven attack for the main city. The attack killed many dwarfs, including his son.
Feeling guilt for surviving, and punishing himself for not being vigilant enough, Bardin took the job of a Ranger. Taking on the job of roaming far away from his hold, where he would dispatch and report on threats well in advance (and remove himself from the pain of facing his family.)
While Rangering, he came across an encrypted map of a lost hold. Discovering it would allow him to reclaim some honor, and searching for it would let him run away from his problems a while longer.
On the way to Ubersreik, he encountered Kerillian who was being attacked by Skaven. Decided to help her out, and continue his journey to Ubersreik, to find a particular book to help him decipher his map. Once there he certainly couldn't let another city (or new friends) die at skaven hands, or let a threat this large possibly reach his home.

Short version: Survivor's guilt, hates rats, stubbornly avoiding his personal problems