Citizenship of the European Union was introduced by the Maastricht Treaty, which was signed in 1992, and has been in force since 1993. European Union citizenship is additional to national citizenship and affords rights such as the right to vote in European elections, European Citizens' Initiative, the right to free movement, settlement and employment across the EU, and the right to consular protection by other EU states' embassies when a person's country of citizenship does not maintain an embassy or a consulate in the country in which they require protection. EU citizens also enjoy legal protections of the EU law, such as protection of personal data.
EU citizenship was first introduced by the Maastricht Treaty, and was extended by the Treaty of Amsterdam. Prior to the 1992 Maastricht Treaty, the European Communities treaties provided guarantees for the free movement of economically active persons, but not, generally, for others. The 1951 Treaty of Paris establishing the European Coal and Steel Community established a right to free movement for workers in these industries and the 1957 Treaty of Rome provided for the free movement of workers and services.
However, the treaty provisions were interpreted by the European Court of Justice not as having a narrow economic purpose, but rather a wider social and economic purpose. In Levin, the Court found that the "freedom to take up employment was important, not just as a means towards the creation of a single market for the benefit of the member state economies, but as a right for the worker to raise her or his standard of living". Under the ECJ caselaw, the rights of free movement of workers applies regardless of the worker's purpose in taking up employment abroad, to both part-time and full-time work, and whether or not the worker required additional financial assistance from the member state into which he moves. Since the ECJ has held that a recipient of service has free movement rights under the treaty and this criterion is easily fulfilled, effectively every national of an EU country within another member state, whether economically active or not, had a right under Article 12 of the European Community Treaty to non-discrimination even prior to the Maastricht Treaty.