If you didn’t know, as you obviously didn’t, one of the main reasons for that whole story was that the Italians wanted to get the whole of Dalmatia in order to enter World War I on the side of the Allies, however the British and French gave Dalmatia to the Serbs with the condition that the Kingdom of Serbs, Croats and Slovenes be formed. But Italy got Istria after the Paris Peace Conference in 1920, which was then predominantly inhabited by Croatian and Slovenian population.
So, what exactly did Mussolini’s fascist regime do during its rule with Istria, which was predominantly inhabited by ”racially inferior” Slavs…?! The correct answer is nothing, except that the street names in Istria were changed and Italianized, that all schools were exclusively in Italian and that all official communication in state institutions had to be in Italian. Moreover, all these changes took place before Mussolini came to power in 1922…