Otto I was the oldest son of Heinrich I (the Fowler), and his wife Matilda, the queen of Germany. His wife was Eadgyth.
King Otto was researching alchemical secrets in order to create a serum that could heal wounds and bring the dead back to life. He at first thought his research was from God, but as his research created only monsters, he was sure it was the Devil leading him astray. Out of this work he ended up creating a giant, uncontrollable abomination. He had the local priest of Wulfburg seal off the creature, burn down the village, and destroy any records or evidence of his research in the hopes of preventing anyone else from discovering the serum or the monsters on the world again.
Behind the scenes Edit
Otto the Great (Otto I) was a historical figure, who actually was the son of Henry (Heinrich) the Fowler. He succeeded his father, when he died.
Otto takes up a similar position to that of his father Heinrich in Return to Castle Wolfenstein, as an architect of ancient evil, although he is not 'resurrected' and fought directly. His monster however is similar to Olaric, in that when it is unleashed it kills Helga von Schabbs, before trying to destroy B.J.
Perhaps it is Otto's serum though unintentionally ended up resurrecting and turning Heinrich I into an immortal undead warlord he became as per RTCW, though Heinrich was himself was using a separate power of the Thule (which itself was not evil per se, though Heinrich used it for evil purposes).