The influence of Georg Simmel on American sociology has been repeatedly pointed out. Robert E. Park and the Chicago School of Sociology in particular owe important impulses to Simmel. It is sometimes overlooked, however, that Simmel himself drew on imported knowledge in his famous essay ‘Die Großstädte und das Geistesleben’ when focusing on the nervousness of the city dweller. This article will therefore tell the brief story of a reciprocal transatlantic knowledge transfer between Berlin and Chicago. It looks at the mutual fascinations and influences, examining both the Americanisation of knowledge and the Europeanisation of experience.