This particular person was apprenticed to the Ho'Din Jedi Knight Iwo Kulka, a Padawan who was a member of the Jedi Order throughout the Clone Wars. These wars took place between the Galactic Republic and the Confederacy of Independent Systems. While serving with Republic clone troopers in 19 BBY, this person and their Jedi Master were caught off guard when Contingency Order 66 was given, which commanded the killing of all Jedi. The clones then turned on them, viewing them as traitors to the Republic, and Kulka managed to get away only due to his student's sacrifice.
The 2005 novel Dark Lord: The Rise of Darth Vader, penned by James Luceno, included a reference to Iwo Kulka's Padawan.