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
Treaty on the Functioning of the European Union Maastricht treaty, which led to the formation of the European Union, saw the EEC Treaty renamed as the Treaty establishing the European Community (TEC) and renumbered. The Maastricht reforms also saw the creation of the European Union's three pillar structure, of which the European Community was the major constituent part. Following the 2005 referenda, which saw the failed attempt at launching a European Constitution, on 13 December 2007 the Lisbon treaty was signed. This saw the 'TEC' renamed as the Treaty on the Functioning of the European Union (TFEU) and, once again, renumbered. The Lisbon reforms resulted in the merging