Allya

Allya was, according to a commonly told story, a female Jedi whom the Jedi Council sent into exile on Dathomir, in 600 BBY. There, she allegedly trained other women in the ways of the Force, ultimately giving birth to the Dathomirians, who eventually splintered into clans of witches. However, the Jedi Council had no such records, and the Dathomirians had other, contradicting stories about their origins. Allya wrote the Book of Law, a book which portrayed the Jedi Order in a bad light, causing the Nightsisters to have little respect for the Order.

Text and facts from the “Allya” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.