Ygraine Pendragon (portrayed by Alice Patten) was the wife of Uther Pendragon and mother of Arthur. She and Uther called upon Nimueh to help her conceive an heir to the throne, as a result of which Ygraine had to die in childbirth so as to preserve the natural balance of life and death. Her brother, Tristan De Bois, swore revenge on Uther and Nimueh later brought him back from the dead as a wraith in order to wreak vengeance. Her death also left Uther with a grudge against all magic, leading him to start his great purge and laws against magic. An apparation of Ygraine appears in "The Sins of the Father", in which Arthur learns the secret of his birth, claiming that Uther went to Nimueh without her knowledge and in full awareness of the price that would be paid for Arthur's birth, but given the presumably false nature of this vision this information is suspect at best.
Ygraine also appears in "The Tears of Uther Pendragon (Part 1)" as one of Uther's hallucinations, grabbing and hanging on to Uther's arm in a well.
She is also the sister of Lord Agravaine
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