Fake news has attracted significant global attention and contestation in recent years. This PhD thesis explores the explosive and oftentimes contradictory rise of fake news and dives into the discursive struggles around journalism, politics, digital media, and liberal democracy that have emerged in its wake. Through a series of interrelated publications – spanning more than five years of research – the thesis examines how and with what consequences journalistic and political actors articulate and dispute the very meaning of fake news. Through a careful and critical mapping of the discursive signification of fake news, the thesis does not only situate the issue in wider political and historical contexts; it also draws out and reflects upon its implications for the future of liberal democracies. Deploying detailed empirical investigations based on news content, textual analysis, and qualitative interviews, the thesis sheds light on discursive struggles around fake news within a number of distinct socio-political contexts. It dives into cases from the US and UK, where fake news first rose to prominence in 2016, as well as from Denmark, where fake news has increasingly become a topic of journalistic and political concern. Drawing on the ontological and conceptual framework of discourse theory, the thesis demonstrates how fake news has come to function as a floating signifier; it is a deeply political concept mobilised within conflicting hegemonic projects with fundamentally different forms of meaning. Having done so, the thesis goes on to show that fake news has not only become central in debates around lies and falsehoods but also for conflicting visions about what ‘politics,’ ‘journalism,’ and ‘liberal democracy’ fundamentally are and ought to be. Indeed, the core argument levelled in this thesis is that fake news has come to function as a prism through which wider struggles over liberal democracy and human co-habitation have become visible at a time of growing political instability. Taken together, the findings offered by the thesis contribute to the field of media and communication studies by addressing a pertinent gap regarding the discursive signification of fake news. Connecting the rise of fake news to structural transformations at the heart of both contemporary media landscapes and liberal democracy, the thesis moves beyond formalistic conceptions of fake news and into the highly conflictual terrain surrounding the concept.