European Communities and a European Political Community failed leading to a return to economic matters. In 1957, the EAEC and EEC were created by the Treaties of Rome. They were to share some of the institutions of the ECSC but have separate executive structures. The ECSC's aim was to combine the coal and steel industries of its members to create a single market in those resources. It was intended that this would increase prosperity and decrease the risk of these countries going to war through the process of European integration. The EAEC was working on nuclear energy co-operation between the members. The
European Economic Community compromise was reached with the Luxembourg compromise on 29 January 1966 whereby a gentlemen's agreement permitted members to use a veto on areas of national interest. On 1 July 1967 when the Merger Treaty came into operation, combining the institutions of the ECSC and Euratom into that of the EEC, they already shared a Parliamentary Assembly and Courts. Collectively they were known as the "European Communities". The Communities still had independent personalities although were increasingly integrated. Future treaties granted the community new powers beyond simple economic matters which had achieved a high level of integration. As it got closer to