The border areas of Italy, Slovenia, and Croatia are characterized by their ethnolinguistic diversity. Moreover, as the current state of research shows, this is also endangered by ethnic self-assessments that deviate from the objective characteristic of language (= diffuse ethnicity). The aim of the current work is to analyze the associated risk potential for the preservation of ethnodiversity in the core area of the examined region. The research results show that the number of speakers in the German language pockets of Friuli is decreasing. However, their existence is not threatened. In contrast, the three German language pockets of Sorica in the Slovenian Julian Alps has practically disappeared – just like the further German language pockets in the same area. Of all the language groups in the study area, Istro-Romanian is the most endangered: the Istro-Romanians in the Čičarija and – more in the south – in the Čepićko Polje, both in Croatian Istria. There, a majority is not particularly interested in preserving their autochthonous Romanian dialect.
