A Jedi Master from Episode I, Master Barrek was given to the Jedi by his parents, who were highly trained professors and had found his Force potential through a blood screening of their own.  Evidently a powerful Jedi, he had become a Master by his mid-30s, and was training Padawan Sha’a Gi when the Clone Wars broke out.  He would not live long after that.  His last mission was an intelligence-gathering mission on the world Hypori, in which he uncovered a large droid factory.  Calling for help, the Council responded with a taskforce which included a contingent of clone troopers, and the Masters Ki-Adi-Mundi and Shaak Ti.  However, almost the entire force was wiped out upon arrival when droid starfighters decimated the landing ships.  Mop-up operations were commanded by none other than General Grievous, and he personally killed Master Barrek.