Alto Adige, an Italian Region on the Alps, offers with its complex linguistic? ethnic composition from which various conflicts derived, a good example in regarding the Europe on the perspective of multi-scale regional identities. This study examines the italianizatioin of Alto Adige during the fascist era, one of the dramatic experiences which exercised a drastic influence on its regional identity. This region, which had been Austrian territory, was annexed to Italy after the World War I. Nevertheless, its habitants could ask for a broad self-government, and Italian government also searched for permitting an autonomy enough to achieve peaceful integration until Mussolini’s seizure of power. But the fascist regime, especially the italianization promoted by Tolomei, gave a decisive trial on the longstanding identity of Alto Adige. While not merely the purification in the public administration, but also italianization of geographical designation, interdiction of german-speaking journals, compulsory education in Italian language, italianization of surname, and destruction of collective memory attached to the historical relics were direct offensives on the native language and culture of Alto Adige, the immigration policy meant an internal colonization through a long-term replacement of inhabitants. Face to these tentatives pursing the regional identity, the inhabitants of Alto Adige did not give up painful but tenacious efforts to preserve the German language and culture. At last, Alto Adige remains nowadays German speaking region, even after the semi-compulsory emigration of German speakers during the World War II. So, we can see that the regional identity of this region based on language and culture is too firm to be disintegrated readily by one or several times of trials.