While the history of the German uranium project during the Second World War has been described in much detail, the funding of nuclear research by the Minister of the Reichspost, Wilhelm Ohnesorge, has found but little attention. The reasons for this were presumably the relative scarcity of documents and an underestimation of the efforts made and the results achieved by the research branch of the Reichspost, the Reichspostforschungsanstalt. The essay attempts to fill this gap in describing how and why Ohnesorge (...) became interested in nuclear physics, how two institutes were set up, and what their objectives were. (shrink)