The aim of the paper is to explore regionalism and the representation of sub-regional identities in a regional institutional-setting. The main research question is how large political regions should be and how various sub-regional identities should be represented in the institutional structure of these regions, mainly in representative bodies as the main democratic institutions of representative democracy. Do larger regions allow the preservation of particular sub-regional identities or are these identities completely absorbed by a wider regional identity? How have sub-regional identities been represented in the institutional structure of wider regions? This is especially important for Croatia as it struggles and repeatedly fails to introdu...