Trumpkin is a Red Dwarf who is suspicious of all things magical and refused to believe in Aslan and the Kings and Queens of old, though he does prove to be a steadfast and loyal companion who gave and accepted advice.
In Prince Caspian, Trumpkin lives with Trufflehunter the Talking Badger and Nikabrik the Black Dwarf. On a stormy night he and his companions found a young Caspian lying unconscious outside their home and brought them in and cared for him until he woke. Although Nikabrik wanted to kill Caspian because he was a Telmarine, Trumpkin and Trufflehunter defended Caspian and allowed him to stay with them. Trumpkin played a main role in introducing Caspian to the Old Narnians and assembled the war council at the Dancing Lawn. He later volunteered to travel to Cair Paravel to search for help, but was later captured by Telmarine guards who tried to drown him. Luckily he was rescued by the Pevensie children, who he was skeptical would be of any help until Edmund beat him in a sword fight. He joined them, and witnessed the battle between King Miraz and High King Peter and fought in the subsequent battle. He was knighted after by Caspian in the Most Noble Order of the Lion.