"Most people enjoy being kicked in the head to be woken each morning. Me, I'm just so picky."
Anders is an apostate mage. He was arrested by templars who intended to cart him back to the Circle Tower; Vigil's Keep was to have been a short stop on the long journey. Unfortunately, the keep was attacked just after the group arrived, and Anders was found standing over the bodies of his captors. He insists they were killed by darkspawn.
Regardless, Anders joined the Warden to defeat the darkspawn in Vigil's Keep.
Anders takes great pride in his appearance and enjoys fine things.
If he undergoes the Joining: Afterwards, Anders was recruited into the Grey Wardens. He survived the Joining.
If he is taken by the templars and given leniency: Although Anders fought alongside (Warden Commander's name) at Vigil's Keep, the Warden-Commander returned the mage to the templars' custody after the battle—with a request that the templars be lenient, given what Anders had done to help the Grey Wardens.
At the end of Freedom for Anders: But the warehouse where the phylacteries were supposedly stored was actually a templar trap. The Warden stood with Anders against the templars, for which the mage was grateful.