The 2014 European Parliament elections were widely construed as a major shock to the political narrative of European integration. A range of parties either skeptical of or openly opposed to the European Union saw major gains, including UKIP in Great Britain, the Front National in France, and the Five Star Movement in Italy. Though a diverse lot, the collective success of these parties triggered concern within pro-European parties and the EU institutions, and featured in the opposition from some heads of government to Jean-Claude Juncker’s appointment as Commission President. A key question, then, is whether these electoral developments reflect a popular rejection of the narrative of integration. The academic study of party-based Euroskepticism can help us answer this, but to do so it must come to terms with the diversity of anti-establishment voices. Building on earlier textual analysis of UKIP, I propose to go beyond the hard/soft Euroskepticism distinction and map these parties in terms of the broader arguments that underpin their claims against the EU. In addition to improving our understanding of the political developments themselves, this can also inform ongoing debates about the Union’s constitutional structure. In particular, I distinguish between populist and nationalist grounds for Euroskepticism, which cast very different lights on the “democratic deficit” and how to fix it
