On April 16th, 2003 the European Union and ten countries—Cyprus*, the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia, and Slovenia—signed a Treaty of Accession, paving the way for those ten nations to become EU member states. The incorporation of what are referred to as the A10 states marked the single largest expansion of the EU since its inception, and has dramatically affected all EU member states, new and old.
The inclusion of seven of these states—the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland and Slovakia—held particular significance having been former members of the Soviet-led Eastern Bloc. With the end of the Cold War and the dissolution of the Soviet Union in 1991, the formal assimilation of these seven central and eastern European nations into the EU has been regarded as an illustration of the end of a bipolar world order and a victory for economic and political liberalism.
Many of the questions raised about the assimilation of the A10 states (and Bulgaria and Romania who joined the EU in 2007) have yet to be resolved. How does the EU deal with the stark relative economic inequality between its member states? How does free movement of people and goods between ever-increasing numbers of nations affect political demographics and economic behavior?
The fallout from the Euro-zone debt crisis, which began in 2009, has made many of these issues important within the domestic politics of many EU member states including Greece, France, the UK and Germany. The topic of immigration in particular has become a hot-button issue in many western European states.
However, the EU has remained positive about its outlook. In 2014, upon the 10th Anniversary of the enlargement, President of the European Commission José Manuel Barroso maintained that all members of the European Union have benefitted from expansion. Barroso noted that trade had tripled between the A10 states and the traditional members of the European Union and that the accession process accounted for half of growth in central and eastern European states between 1994-2008. The European Union makes up about 23% of global GDP.
*Cyprus, a divided nation, has not fully joined the EU. Northern Cyprus, which has rejected the authority of the Republic of Cyprus and European membership, is not recognized by the EU as a separate state. For more information about Cyprus' complicated relationship with the EU, click here.