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European Union Law

Introductory Resources on European Union Law

Here are some of the Law Library's introductory resources on European Union law. Search the UIUC catalog for additional resources.

Introduction to the European Union

The European Union is a unique political entity comprised of 28 independent nations that have established common institutions to which they have voluntarily delegated some of their sovereignty so that decisions on specific issues of common interest can be decided at a higher, supra-national level.

The Member States of the EU

Map © Wikimedia (  Used with permission.

The countries that comprise the European Union are known collectively as the Member States.  The founding members of the European Economic Community, the EU's institutional predecessor, were Belgium, France, (West) Germany, Italy, Luxembourg, and the Netherlands.  The first expansion of the EEC took place in 1973 when Denmark, Ireland, and the United Kingdom became Member States.  Greece joined the EEC in 1981, followed by Spain and Portugal in 1986.  

In 1993, with the implementation of the Maastricht Treaty, the EEC changed its name to the European Union.  Austria, Sweden and Finland joined the EU in 1995.  The most notable enlargement occurred in 2004 with the accession of 10 new Member States, most of which were formerly members of the Soviet Bloc.  They included the three Baltic states (Estonia, Latvia, and Lithuania), the Czech Republic, Hungary, Poland, Slovakia, and Slovenia, as well as Cyprus and Malta.  Bulgaria and Romania joined the EU three years later.  Croatia became the 28th Member State on July 1, 2013.

In the 2010s, starting in 2016, the United Kingdom initiated a referendum vote on whether or not to invoke Article 50 of the Treaty on European Union and thereby leave the European Union itself. The referendum was held on June 23, 2016 and the results were that the UK decided to invoke Article 50 in a 52% - 48% vote. Throughout the next five years, until December 31, 2020, the UK government and the EU negotiators who were meeting to hammer out the withdrawal agreement of the UK in a way that attempted to deal fairly for both sides and that touched on issues of trade, fundamental European rights, tariffs, etc. However, this process was turbulent over the four-year period of negotiation, and led to the departure of two prime ministers and much public debate. Although the UK is now no longer a part of the EU Customs Union nor part of the EU as a whole, the latest negotiation concluded on May 1, 2021.

Free Resources on the European Union

Portal to the European Union at Illinois