The Merger Treaty, signed in Brussels on 8 April 1965, replaced the separate executives of the three European Communities (ECSC, EEC and Euratom) with a single Commission and a single Council. It entered into force on 1 July 1967.
- Official name
- Treaty establishing a Single Council and a Single Commission of the European Communities
- Signed
- 8 April 1965, Brussels, Belgium
- In force
- 1 July 1967
- Signatories
- 6 states
By the early 1960s, the six founding countries were members of three separate communities: the European Coal and Steel Community (1952), the European Economic Community and Euratom (both 1958). Since 1958, the three already shared a Parliamentary Assembly and a Court of Justice. But each still had its own executive: the High Authority for the ECSC, and a Commission each for the EEC and Euratom, as well as separate councils of ministers.
The six decided to simplify this structure. They signed the Treaty establishing a Single Council and a Single Commission of the European Communities in Brussels on 8 April 1965. It entered into force on 1 July 1967.
What it changed
The treaty merged the three executives into one Commission of the European Communities and the three councils into one Council of the European Communities.
It did not merge the three communities themselves. The ECSC, the EEC and Euratom remained legally separate, each based on its own treaty, but from 1967 they were run by the same institutions. This is why people began to speak of “the European Communities” in the plural. Competences and voting rules did not change.
Example
The Commission that took office in July 1967 was the first single Commission, responsible for coal and steel, the common market and nuclear energy at the same time. The European Commission and the Council of the EU that exist today are its direct successors.
The European Parliament describes the Merger Treaty as the step that completed the institutional unification of the three Communities, begun in 1958 with the shared Assembly and Court. The EU’s official history summarises the result in simple terms: from 1967, the European Communities had a single administrative arm, the Commission, and a single executive, the Council.