Constitutional Issues of the Banking Union, between European Law and National Legal Orders

European history has always been characterized by a strong link between banks and States and, more generally, between banks and politics. National banking systems, therefore, have always been one of the forms of expression of sovereignty. This setting is seriously called into question by the Banking Union project, which has been recently implemented in Europe. Given the importance of the issue, this should be studied not only from the perspective of economics and regulatory studies, but also from the perspective of constitutional law. The paper is divided into eleven parts. The first part aims at reconstructing the historical and economic conditions that have led to design a project of Banking Union.The second part highlights the regulatory asymmetry between euro-area countries and non-euro-area countries. While, in fact, some institutions (such as the EBA) operate across the whole Europe, the Banking Union concerns only those countries that have adopted the euro as their currency.