During the post-1989 period, various forms of nationalism came back to haunt Eastern and Central Europe. Why are they so virulent and so dangerous in modern times? Since the modernization of the nineteenth century, language has not only been a normal means of communication and a substantial part of human identity but also plays an increasingly important political role: public opinion, media and politics all depend on a common language, which tends to become the language of the state. The process of linguistic homogenization by the state, which had already been completed in Western Europe, failed in this context. Europe will therefore have to come to terms with its linguistic diversity in the future. Is this nothing more than a hindrance?