Forgotten Visions: Imagining the Nature of European Union Law (1950-1965) . My research project aims to provide the first intellectual history of European Union law in its formative period from 1950 to 1965. Based on an interdisciplinary methodology that combines archival research and intellectual history, this project will map competing visions about the nature of EU law in the early period of the European integration process, retrace the intellectual origins of those ideas and situate them in their socio-political context. This project thereby retrieves the ‘forgotten visions’ on the nature of EU law that were marginalised in the aftermath of the European Court of Justice’s foundational rulings in the early 1960s. When the Court declared EU law to form a ‘new legal order’ in van Gend en Loos and Costa v ENEL it made a fundamental decision about the course of the legal integration process, as exemplified in Judge Lecourt’s rhetorical question: ‘Quel eut été le droit des Communautés sans les arrêts de 1963 et 1964?’ While Lecourt implied that without the Court's intervention the integration project would have faltered, I propose to take his rhetorical question seriously and use it as a starting point to retrieve the various alternative visions of the nature of EU law. My aim is to question the assumption that the Court's intervention was inevitable and without alternatives. In doing so, I hope to enhance the scholarly understanding of EU law’s historical development and to open pathways to rethink the authority of EU law at a time when the EU is increasingly subject to contestation and critique.