Treaties of the European Union the Functioning of the European Union (originally signed in Rome in 1957 as the Treaty establishing the European Economic Community, aka The Treaty of Rome), lay out how the EU operates, and there are a number of satellite treaties which are interconnected with them. The treaties have been repeatedly amended by other treaties over the 65 years since they were first signed. The consolidated version of the two core treaties is regularly published by the European Commission. The two principal treaties on which the EU is based are the Treaty on European Union (TEU; Maastricht Treaty, effective since 1993) and
European Communities EEC was to create a customs union and general economic co-operation. It later led to the creation of a European single market. The EEC became the European Community pillar of the EU, with the ECSC and EAEC continuing in a similar subordinate position, existing separately in a legal sense but governed by the institutions of the EU as if they were its own. The ECSC's treaty had a 50-year limit and thus expired in 2002, all its activities are now absorbed into the European Community. The EAEC had no such limit and thus continues to exist. Due to the sensitive