Taran of Caer Dallben
Taran of Caer Dallben is the young protagonist in "The Book of Three". He is an Assistant Pig-Keeper, and is very heroic and courageous. Taran's appearance is never described, but we are told that he is tall, somewhat lanky, and strong. Throughout the book, Taran learns to embrace who he is and becomes more comfortable in his own skin.
Princess Eilonwy
Princess Eilonwy is a pretty, candid, and kind-hearted princess. She has blue eyes and long, red-blonde hair, and has soft features. She is the daughter of Angharad of the Royal House of Lyr. She is strong, can fight and do lesser enchantments. Taran befriends her when they meet at the Spiral Castle where they both are prisoners, in each their sense.
Prince Gwydion Son of Don
Gwydion is a prince, warrior and an enchanter. He carries the mighty and magical sword of Dyrnwyn, and rides of the white mare called Melyngar. He is heroic and legendary, and very masculine. The prince met Taran when they both were looking for the Hen Wen, and they were both captured by the evil sorceress.
Hen Wen
The Hen Wen was a "white" pig owned by Coll Son of Collfrewr. The pig had oracular abilities and could tell the future and reveal secrets. When the Hen Wen, who is very important for the people of Caer, disappeared, Taran decided to find it. That is the beginning of the story of Taran and his many quests.