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
Maastricht Treaty Maastricht Treaty The Maastricht Treaty (officially the Treaty on European Union) was signed on 7 February 1992 by the members of the European Community in Maastricht, Netherlands to further European integration. On 9–10 December 1991, the same city hosted the European Council which drafted the treaty. The treaty founded the European Union and established its pillar structure which stayed in place until the Lisbon Treaty came into force in 2009. The treaty also greatly expanded the competences of the EEC/EU and led to the creation of the single European currency, the euro. The Maastricht Treaty reformed and amended the treaties