Raiden , real name Jack, was the adopted son of Solidus Snake, after his biological parents were both killed by Solidus early in his childhood. From an early age he was trained to be a soldier and earned several nicknames due to his skill in combat. Sometime after this, he was outfitted with a cyborg exoskeleton to keep him alive after torturous experiments by the Patriots in which they removed his spine and part of his head.
Jack would grow up to suppress the memories about his terrible childhood, burying the memories of his bloody past, though he still suffered from nightmares of his past nearly every night. Now living a life in the United States, Jack joined the military where his admirable skills were at first recognized by the U.S. Army's Task Force XXI. From there he participated in three hundred VR simulations, such as a re-creation of the Shadow Moses Incident that took place a few years earlier.
Jack met Rosemary and had an argument about King Kong. After they parted ways, they met again afterwards, shocked that they worked in the same place. Eventually, Jack grew to love Rose deeply, but his harsh experiences had left him melancholic and emotionally distant, and he constantly shut her out of his problems. However, all of this drama was a ruse by the Patriots to gain control of Raiden's life, with Rosemary as a Patriot spy.