The English Defence League (EDL) is the biggest populist street movement in a generation. Yet the make-up of the group and what its members believe remain a mystery because it has no formal joining procedures or membership list and much of its activity takes place online., While leaders of the EDL claim they are a pluralistic, liberal movement that is fighting Islamic extremism, chants heard at demonstrations and the vitriol frequently posted on the EDL’s chat forums suggest otherwise. It is in this context that we have undertaken the first ever large-scale empirical study of the EDL, which comprises responses from 1,295 sympathisers and supporters, and includes data on their demographics, involvement in EDL activity, political attitudes and social views. The results show that, although the EDL is usually understood as an anti-Islamic or anti-Islamist demonstrating group, the reality is more complex., Supporters are characterised by intense pessimism about the UK’s future, worries about immigration and joblessness. This is often mixed with a proactive pride in Britain, British history and British values, which they see as being under attack from Islam. Although their demonstrations have often involved violence and racist chants, many members are democrats who are committed to peaceful protest and other forms of activism., The collection of large amounts of data from social media presents new opportunities for social research to understand the relationship between off- and online activity. As more movements combine – and blur – virtual and real protest, these questions will become increasingly urgent and important. These surveys, collected through Facebook using a new methodology, offer new ways forward in exploring this challenge.