In 19 BBY, Bacara was the commander of the Galactic Marines. He and the Marines fought on Mygeeto alongside jedi master Ki-Adi Mundi against the Separatists droid armies.
Soon Bacara would come to receive order 66 from Republic chancellor Palpatine, meaning that the clones would turn against their jedi generals. Therefore Bacara and several other Marines formed from behind Ki-Adi Mundi and shot him down, with Mundi barely getting the chance to defend himself properly with heat from both sides.