The kapitän was a member of the Nazi party who had impregnated the character which B'Elanna Torres was playing. A brutal man and very much believing in Adolf Hitler's ideals that Germans are the "master race" and having "pure blood", causing Karr to criticize him for "underestimating his prey". He was in charge of a province in France. He was ultimately killed by Klingons, who were part of another simulated hunt scenario, in the final battle for the town. (VOY: "The Killing Game", "The Killing Game, Part II")
The kapitän was played by J. Paul Boehmer. Kapitän actually refers to a naval captain in the German military. Since he was an SS officer, the correct rank would have been "Hauptsturmführer" or at least "Hauptmann" to reflect the army branch. In fact, he wore the rank insignia of a "Hauptsturmführer".