Hamadryads are beautiful tree nymphs or spirits that live throughout the world of Narnia.They do not live in Oak, Elm, Holly, Rowan, Beech, Silver Birch, Larch, Willow and Blossom trees. They are a specific species of dryad, which are a particular type of nymph. Hamadryads are born bonded to a specific tree. Some believe that hamadryads are the actual trees, while normal dryads are simply the entity, or spirit, of the tree. If the tree died, the hamadryad associated with it died as well.
Hamadryads first appeared in The Magician's Nephew when they were created by Aslan's song which also created Narnia and the other creatures. They all gathered as a council and joined the coronation of Frank I and Helen, the first king and queen of Narnia.
Hamadryads hid inside their trees during the Long Winter that the White Witch created. Most were turned to stone and, after being restored by Aslan, many fought in Aslan's Army in the First Battle of Beruna against the White Witch's Army for the freedom of Narnia.
After the invasion by the Telmarines, Hamadryads hid in the land again until the time of the Narnian Revolution. When Narnia began to be ruled by Caspian X, who was a Telmarine but loved the Old Narnians, the Hamadryads began to spread around happily. Near the time of the Last Battle, Hamadryads began to die as their trees were cut and entered into Aslan's Country.