This article aims at reconstructing the origin and evolution of the Estonian politicaladministrative reform of 2017. In this reform process, which redefined the institutional framework of the country, was relevant the role played by the European Union in influencing such changes. The dynamic approach of Anssi Paasi’s studies on territorial institutionalisation will be here considered, concerning the different historical phases that led the country to reaffirm its national identity after the long period of Soviet occupation (1940-1989). The reform analysed in this case study confirms the extent of the interventions on the administrative framework, which are the result both of a process rooted in the transfer of powers and of Estonia’s entry into the European Union which has long called for rescaling policies.