text: Agreement remained elusive and a seat had to be found before the institutions could begin work, hence Luxembourg was chosen as 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 (Germany), which would serve as a "European District", but this did not occur.
  The 1957 Treaty 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). Discussions on the seats of the institutions were left until the last moment before the treaties came into force, so as not to interfere with ratification.
  Brussels waited until only a month before talks to enter its application, which received unofficial backing by several member states. The members agreed in principle to locate the executives, Councils, and the assembly in one city, though could still not decide which city, so they put the decision off for six months. In the meantime, the Assembly would stay in Strasbourg and the new Commissions would meet alternatively at the ECSC seat and at the Château of Val-Duchesse, in Brussels (headquarters of a temporary committee). The Councils would meet wherever their Presidents wanted to. In practice, this was at Val-Duchesse until autumn 1958 when it moved to central Brussels, at 2, /.