Hagen was a Barbarian from Germania who was sold to Proximo, a wealthy slave owner. He, being a talented fighter, was designated by Proximo to test any new slave's fighting ability.. Hagen befriended the Numidian tribesman Juba and the ex-Roman General Maximus Decimus Meridius. In the game where they did a Battle of Carthage Reenactment, Hagen helped Maximus create an anti-cavalry formation against the "Scipio Africanus" team's chariots. Hagen though, was wounded by a Charioteer's arrow to his thigh. He would have been killed, had Maximus not pushed him out of the way of an oncoming chariot.
He joined Maximus' Army of Gladiators who were going to defend Proximo's Gladiator School from the Emperor Commodus. Hagen and several gladiators charged the enemy, and after putting up a valiant fight, being hit by approximatley 7 arrows, he was eventually killed.