German twentieth-century history is characterized by stark changes in the political system and the momentous consequences of World Wars I and II. However, instead of uncovering specific kinds or periods of “Kaiserreich science,” “Weimar science,” or “Nazi science” together with their public manifestations and in such a way observing a narrow link between popular science and political orders, this paper tries to exhibit some remarkable stability and continuity in popular science on a longer scale. Thanks to the rich German history of scientific leadership in many fields, broad initiatives for science popularization, and a population and economy open to scientific progress, the media offered particularly rich popular science content, which was diversified for various audiences and interests. Closer consideration of the format, genre, quality, and quantity of popular science, and of the uses and value audiences attributed to it, along with their respective evolution, reveals infrastructures underpinning science communication. Rather than dealing with specific discourses, the conditions of science communication are at the center of this article. Therefore I focus on the institutions, rules, laws, and economies related to popular science, as well as on the philosophical, moral, and national propositions related to it, and also on the interactions among this ensemble of rather heterogeneous elements. This approach allows a machinery of popular scientific knowledge to be identified, in Foucauldian terms a dispositif, one which is of a particularly cultural nature.