A Dunadan Warrior from Sarn Erech in Morthond Fief in Lamedon, Derufin was the younger son of Duinhir. He and his brother Duilin served under their father as commanders of two companies of bowmen in the Steward's army at the Battle of Pelennor Fields in T.A. 3019. They both perished in the attack against the Mumakil (Oliphaunts).