European Union and West Germany signed the Treaty of Rome, which created the European Economic Community (EEC) and established a customs union. They also signed another pact creating the European Atomic Energy Community (Euratom) for co-operation in developing nuclear energy. Both treaties came into force in 1958. The EEC and Euratom were created separately from the ECSC, although they shared the same courts and the Common Assembly. The EEC was headed by Walter Hallstein (Hallstein Commission) and Euratom was headed by Louis Armand (Armand Commission) and then Étienne Hirsch. Euratom was to integrate sectors in nuclear energy while the EEC would develop
European Coal and Steel Community their fields rapidly expanded and the EEC became the most important tool for political unification, overshadowing the ECSC. Despite being separate legal entities, the ECSC, EEC and Euratom initially shared the Common Assembly and the European Court of Justice, although the Councils and the High Authority/Commissions remained separate. To avoid duplication, the Merger Treaty merged these separate bodies of the ECSC and Euratom with the EEC. The EEC later became one of the three pillars of the present day European Union. The Treaty of Paris was frequently amended as the EC and EU evolved and expanded. With the treaty due