This article analyses mediated invocations of the people' or the public' in the Dreyfus Affair, and orients this historical analysis towards contemporary debates on public spheres and digital media. If the ideal Habermasian public sphere never historically existed, how did the imperfect' public spheres of the past nevertheless contribute to democratic political participation? The late 19th century is a particularly salient point of comparison, being a time of transition from one set of media technologies and notions of publics to another. Focusing on newspapers, posters and other print-based communicative practices, I identify two general and consistent modes by which the other-public' is produced: (1) the other' audience as the target of persuasion, influence and commentary, and (2) the speaker as a distinct other' from the crowd. This othering was not a pathological barrier to full participation', but a constitutive part of publicity in an age of nascent mass media.