This article analyzes the making of a novel consciousness of historicity in Germany around 1800, one that regarded mountains as vaults of a shared and palpable past. Revisiting a paleontological debate about the origin of large mammal bones found in caves, it reads the science of Johann Christian Rosenmüller (1771–1820) as a social and political accomplishment. By attributing the fossils to an indigenous "cave bear," and communicating an elite scientific debate to a lay audience, Rosenmüller presented an account of Germany's primordial past that fed seamlessly into its present, nurturing an idea of nationhood grounded in the (sub)soil.