Andrzej Sapkowski: "When I created Yennefer's character I wanted Geralt to fully grow, but then I decided to make things complicated. I created a female character who refuses to be a fantasy stereotype. To please the reader."
Yennefer, born on Belleteyn in 1173, was a sorceress who lived in Vengerberg, the capital city of Aedirn. She was Geralt of Rivia's true love and a mother figure to Ciri, whom she viewed like a daughter to the point that she did everything she could to rescue the girl and keep her from harm.
She was a former royal advisor to king Demavend of Aedirn, a close friend of Triss Merigold, and the youngest member of the Supreme Council of Sorcerers within the Brotherhood of Sorcerers.
After its fall, the Lodge of Sorceresses attempted to recruit her, but they didn't see eye to eye as the Lodge wanted to advance their own political agenda by using Ciri.
Born in 1173, Yennefer had a rough childhood from the moment she was born, having been born a hunchback. Her father immediately detested her due to this deformity and blamed Yennefer's mother for it, claiming it was through her side, with mages and elven blood, not to mention her having had an abortion before, that caused the deformity.
Her mother initially tried to protect Yennefer, believing it was by the will of the gods, but her father still struck Yennefer until one day he left them both for someone else. After this, her mother, upset that her husband had left, also began to beat her own daughter. During the Battle of Sodden Hill she was blinded by Fringilla Vigo, a Nilfgaardian sorceress.
She gave her motherly love to Ciri - the child destined for Geralt by the Law of Surprise - teaching her about magic while in Ellander, at the Temple of Melitele under the watchful eye of Nenneke.