Tan Tengo was a female Sullustan who lived during the Republic Dark Age. She was born on the planet Darkknell, which had become the capital of the Sith Lord Daiman's princedom known as the Daimanate by 1032 BBY. At a young age, she was orphaned and was raised by her grandfather Gub Tengo. For much of her childhood, Tan lived under Sith rule. In 1032 BBY, Tan's life changed after she came into contact with the undercover Jedi Knight Kerra Holt, who had assumed the cover identity of an itinerant worker and private tutor. While tutoring Tan, Kerra however was spying on the Black Fang research installation where Daiman was developing a prototype warship known as a Convergence Tactical Assault Vehicle. Kerra destroyed the facility.