This contribution insists on the difference between populism and the radical right in Europe as two overlapping but different phenomena. The aim is to analyse the multiple explanations for the rise of populist radical right parties by focusing on cleavages and in taking the French case of the Front National as the paradigm. Although economic reasons feature among the deeper explanations for the rise, they are not sufficient. These populist parties are identitarian movements. Cultural issues such as immigration and political culture constitute a kind of ‘filter’ on their way to success.