Brussels and the European Union a provisional seat, though with the Common Assembly in Strasbourg as that was the only city with a large enough hemicycle (the one used by the Council of Europe). This agreement was temporary, and plans were set to relocate the institutions to Saarbrücken which would serve as a "European District", but this did not occur. The 1957 Treaties of Rome established two new communities, the European Economic Community (EEC) and the European Atomic Energy Community (Euratom). These shared the Assembly and Court of the ECSC but created two new sets of Councils and Commissions (equivalent to the ECSC's High Authority).
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