European citizenship was established by the Treaty of Maastricht in 1993.
EU citizenship prevails over national citizenship in the same way as, for example, German citizenship prevails over that of Bavaria. In the EU, Bavarians have a triple citizenship: of Bavaria, Germany, and the EU.
The future
The EU Constitution proposes a dual citizenship so that EU citizens will be both national and EU citizens. Art. I-8 defines the “Citizenship of the Union”.
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