Gwen was born in the Dryad Forest, right outside Dalasia, and was seen as a monster. Repulsed by the young baby's appearence, the women who delivered Gwen appealed to her mother, the Dryad queen, Floria, to drown her. Floria loved Gwen, though, and spared her life.
Queen Floria grew weaker and weaker, until at last on Gwen's 7th birthday, she died.
On Gwen's 8th birthday, her father became a Seer, and left her and her 15 year old sister, Gwyn, to rule the forest.
Gwyn and Gwen remained in the forest until Gwen was called to the Mountain of the Seers by her father. Gwen followed her father's instructions to not reveal her rank to her new companions, and it was only her companion Grollus who knew who Gwen was.