Since the beginning of Lotman's project of a semiotics of culture(s), the concept of non-culture, or that of lack of culture, have played a fundamental role. Indeed, in the frame of Lotman's theory, the presence of a dimension of non-culture, or lack of culture, is unavoidable for the definition of culture itself. Post-Lotmanian semiotics deepened the study of the internal dynamics of the cultural semiosphere, but very rarely tackled the question of non-culture, or that of lack of culture. The article aims at investigating the frontiers between semiosphere and semio-chaos, or between semio-sphere and semio-nothing, meditating, in particular, on the following questions: a) How can "barbarity" be characterized in the frame of a semiotics of culture?; b) Is barbarity simply a figure of lack of culture, or is it something more? And c) Can a typology of non-cultures be elaborated, in the same way as Lotman and Uspenskij elaborated a typology of cultures? What would the role of "barbarity" be in such a typology?