The expansion of the EU brought the uneven development of its parts to the fore. The cohesion policy became therefore one of the Union’s most important policies, which can be seen in the increasing EU budget allocations for both the past (2014–2020) and present programming period (2021–2027). The cohesion policy is financed through three main funds: the European Regional Development Fund (ERDF), the Cohesion Fund (CF), and the European Social Fund (ESF). The regional policy has been developing in the last few decades based on the principles of regional autonomy, political decentralization and subsidiarity, financial autonomy, solidarity, and fiscal equalization. The Republic of Croatia, as a Member State of the European Union, falls within the scope of all forms of regionalization: macro-regional strategies, transnational, cross-border and interregional cooperation, the assisted areas program, the program for mountainous and hilly areas, the program for Croatian islands, integrated territorial investments, the small town regeneration program, individual approaches to the development of NUTS II regions, etc. Encouraging regionalization aims to decentralize European countries. The strengthening of regions weakens states, and it creates space for the creation of a centralized Europe. The need to weaken national identities and to create a single European identity in order for Europe to achieve sustainable economic growth is called into question.