Riordan

                 "Be firm in your beliefs, protect people from their own ignorance, and be as loyal as you can to your brothers, even knowing that you'll share their deaths."

Riordan is a senior Grey Warden who was born in the Fereldan teyrnir of Highever. Riordan joined the Grey Wardens at the same time as Duncan and they have been comrades for a long time. Riordan was in Ferelden shortly before the Blight and even watched Alistair's Joining but had to leave for Orlais before the Battle of Ostagar. He was caught trying to regroup with the surviving Wardens by Arl Rendon Howe. He was captured and held in the Arl of Denerim's Estate Dungeons. He is found towards the end of the game and helps the player rally Ferelden against the Darkspawn. He also explains the reason that Grey Wardens are required to end a Blight. Riordan dies in the final battle after wounding the Archdemon. 
 
After freeing him you can talk to Riordan to get more history about the Grey Wardens and about Duncan. Riordan can help the player by giving them the location of the Grey Warden Vault in Denerim. It contains some good weapons and armor and also has Duncan's Shield which can be given to Alistair as a gift.