Éowyn was a daughter of the House of Eorl and the niece of Chieftain Theoden; the daughter of Theodwyn (sister to Theoden) and Eomund, and the twin sister of Éomer. When she was only seven years old,when her father was killed in battle and her mother died of grief.
Éowyn and Éomer were raised in her uncle’s household as if they were his own children.
Morgana sent her spies to Theoden’s court, the most famous of them only known as Wormtongue, who tried to persuade Theoden not to send his famed Horsemen to Arthur’s aid. Éowyn exposed his lies and accused of him of inappropriate behavior. Éomer threw him off the castle battlements, killing him instantly.
When Chieftain Theoden discovered the deception, he sent the famed Riders of Rohan under the leadership of his nephew Éomer, to help Arthur Pendragon in his struggle with Mordred. Not be left behind, Éowyn disguised herself as a soldier and rode with her brother into the fight at the Battle of Camlann.
During the battle, she killed Morgana for crimes against her family. When Mordred saw his mother’s death he attacked Éowyn, only to be slain by Éomer in defense of his sister.
After the battle and the subsequent ‘Death of Arthur’, Éomer encourages Éowyn to go to the Queen’s side, to help her with the loss of the King, only to discover Severus attending Arthur’s wound. She was taken into Guinevere’s confidence and becomes one of her trusted servants.
A year later, she was Turned on the same day as her brother.