Not much is known of Klaudia's past. She is the partner of a German pilot, reduced to a vegetative state during WWII.
By a matter of coincidence, she is tested for the special blood, and is a powerful match.
She becomes Battleship Sieglinde, an immensely powerful super being, and one of three Battleship Class Ubermensch who turn the tide of the war back in favour of Nazi Germany.