Agent California was a rogue Spartan who got recruited into Project Freelancer. His real name is Commander Jacob Shepard. He came from a planet in the future that was invaded by the reapers. He eventually got sent back in time after finally stopping the reapers, and found his way to Project: Freelancer, and used them to get back to his own time.
Cal's armor was a hodgepodge of different armors using a Security Helmet, Aviator chestpiece, and Rogue shoulder-pads. It had several different abilities.