History of the European Union Europe Declaration (1951). This principle was at the heart of the European Coal and Steel Community (ECSC) (1951), the Treaty of Paris (1951), and later the Treaty of Rome (1958) which established the European Economic Community (EEC) and the European Atomic Energy Community (EAEC). Both the ECSC and EEC were later incorporated into the European Union while the EAEC maintains a distinct legal identity despite sharing members and institutions. The Maastricht Treaty (1992) created the European Union with its pillars system, including foreign and home affairs alongside the European Community. This in turn led to the creation of the single
European Economic Community the European Union, though limited in some areas due to the pillar structure. Despite this, Parliament in particular has gained more power over legislation and security of the Commission. The Court was the highest authority in the law, settling legal disputes in the Community, while the Auditors had no power but to investigate. The EEC inherited some of the Institutions of the ECSC in that the Common Assembly and Court of Justice of the ECSC had their authority extended to the EEC and Euratom in the same role. However the EEC, and Euratom, had different executive bodies to the ECSC.