An unidentified princess was a seer and the lover of Jedi Grandmaster Damien Nightblade. At some point in the thousands of years prior to his death in 41 BBY, the princess came to Nightblade and told him that she had had a vision of her own death. Knowing that her visions always came true, Nightblade swore that he would find a way to stop himself and the people he cared about from dying. He did discover the secrets of immortality, but the princess died before he could save her.
After the princess died, Nightblade began to fall to the dark side of the Force. He eventually became Darth Plagueis, the Dark Lord of the Sith. In 41 BBY, Plagueis' last thoughts were of the princess before he was stabbed to death by his apprentice.
- Star Wars: The Tragedy (First mentioned)