The cultural turn in copyright law identified authorship as a rhetorical construct employed by economic interests to strengthen claims to property rights. Grassroots intellectual property political movements have been seen as both a means of countering these interests’ everexpanding proprietary control of knowledge and establishing a more public regarding copyright system. This Article examines one of the most notable intellectual property political movements, the emergence of late nineteenth-century agitation to provide copyright protection for foreign authors as a social movement. It places this political and legal activism within the larger framework of Progressive Era reform. During this period, activists promoted the idea of the public — and not simply the author — as primary to the workings of American copyright. The framing of the purposes of copyright, the appeal to a broader public, and the complex negotiations surrounding the passage of an international copyright act after a long period of gestation was formative to the creation of modern United States copyright law. Ironically, the movement for international copyright also sharpened the identification of interest groups. The first modern American comprehensive copyright legislation, the 1909 Copyright Act, was drafted by gathering together these groups for negotiations remarkably similar in style to those which led to the protection of the rights of foreign authors — but which would strongly embrace a proprietary model.