Born in Germany, he was a Nazi and member of the Waffen-SS during World War II. After the war, he emigrated to Auckland with his family.
He was angry and abusive towards his family, to the point that Elsa broke her ribs and lost a spleen. He also broke Rita's wrist once.
In her teens, his daughter Rita fell in love with Ted West. Dieter strongly disapproved of his daughter going after a criminal communist, so this lead to many heated arguments. In one of these, Rita was about to leave, but Dieter threatened to shoot her with his Luger and locked her in the shed in the garden.
Ted eventually came to look for Rita and rescued her from the shed. Dieter tried to stop him, but Elsa held him at gunpoint with his own Luger. Dieter said "If you go with him, you never come back," and she never did. The only contact she made was a call on July 29, 1961, to tell them that she had married Ted.
By 1981, he had suffered a stroke which rendered him incapable of moving and talking, requiring his wife to be his caretaker. Rita came back to see them.