Elena is described as a very beautiful woman with a young face, long, silver hair and pointy ears. Celaena described her as though she was bathed in moonlight.
Elena was a half fae, daughter of King Brannon of Terrasen, and later wife of Gavin Havilliard, about one thousand years before the events of the Throne of Glass. She had helped her husband to defeat the evil Valg King Erawan, using a magical jewel, later on called the Eye of Elena. When she would wear it, Erawan couldn't kill her, whilst she whispered his name and put an end to him. They are buried in a tomb hidden in a hidden passage. Prince Dorian particularly liked to read legends about her and Gavin.
Celaena saw Elena on a tapestry which covers the secret passage. Elena haunts her in her dreams and tells her she must win the tournament, and defeat the evil that remains hidden in the royal palace. She also helps Celaena in one of the tournament tasks, telling her to look "right", so that she places the cups filled with particular types of poison in the right order.
.Elena seemed to be at peace now that Celaena knew what evil lurked in the glass castle, but there was still much work to be done.
Elena breaks the lock 1000 years earlier using it to win a battle and lock away evil, but as a payment of doing so and ruining the one shot the world had at sending evil back to where it came the Gods make elena raise guide and prepare 'sheep for the slaughter' to sacrifice and create a new lock. This whole time Elena has been raising Celaena up to become a sacrifice.
- Elena is an Italian/Spanish form of Greek Helénē, possibly meaning "torch".