In the 1920s, and especially during the Third Reich, the ‘lunatic fringe’ of prehistoric archaeology – in this case a group of pseudoscientists that used and created archaeological evidence to found their religious and political visions of the early past – has had a great influence on German archaeology. This group, often called archaeological Schwarmgeister (‘fanatic dreamers’), attempted with varying success to gain influence by occupying party positions and by initiating excavations that might not have occurred otherwise. By focusing on the activities of two pseudoscientists – Wilhelm Teudt and Hermann Wille – as case studies, it becomes clear that they reinforced the existing division (Ahnenerbe versus Amt Rosenberg) within professional archaeology. The reactions from academic archaeologists turn out to have been diverse. The theories of Wilhelm Teudt on the Germanic Externsteine were accepted by some professional archaeologists. At the megalithic graves in the Oldenburg area, where Hermann Wille was active, this did not happen. After 1945 their work was used in the accusations that the assistants of Amt Rosenberg especially had been involved in unscientific research. This accusation did not correspond with contemporary reality but was the result of the struggle for power and influence within the group of academic archaeologists that continued in post-war Germany.