Regionalism emerges as the aspiration and resistance of the periphery towards the center of the state. It is characterized by decentralization, uniqueness and democracy. In Istria, during the 1990s, in the process of creating various political options at the state level, the Istrian Democratic Parliament was established. In its program declaration, among other things, it advocates a multi-party system, regionalism, bilingualism, decentralization, anti-fascism. In the referendum for Croatian independence, the citizens of Istria had a turnout of more than 80%, and about 90% of those who voted at the county level opted for independence. Furthermore, the analysis of the three censuses (1991, 2001, 2011) leads to the conclusion that the number of regionally declared people correlates with the instructions of the Istrian Democratic Parliament. In the 1991 census, as many as 18.2% of the population declared themselves as regionals, while ten years later only 4.3% declared themselves as such. When the 2011 census is taken into account (the number of regionals increases again to 12.1%), it can be seen that this is a variable item. In the relations between the leading regional option and the ruling Croatian Democratic Union, there have been conflicts and exchanges of opinions from the 1990s until today, which is not surprising, since every regional option exists precisely because it is dissatisfied with the central option in its country.