Central and Eastern Europe Soviet Union; the independent states in former Yugoslavia (which were not considered part of the Eastern bloc); and the three Baltic states – Estonia, Latvia, Lithuania (which chose not to join the CIS with the other 12 former republics of the USSR). The CEE countries are further subdivided by their accession status to the European Union (EU): the eight first-wave accession countries that joined the EU on 1 May 2004 (Estonia, Latvia, Lithuania, Czech Republic, Slovakia, Poland, Hungary, and Slovenia), the two second-wave accession countries that joined on 1 January 2007 (Romania and Bulgaria) and the third-wave accession country that
2007 enlargement of the European Union 2007 enlargement of the European Union The 2007 enlargement of the European Union saw Bulgaria and Romania join the European Union (EU) on 1 January 2007. Together with the 2004 enlargement of the European Union, it is considered part of the fifth wave of enlargement of the European Union. Romania was the first country of post-communist Europe to have official relations with the European Community. In 1974, a treaty included Romania in the Community's Generalized System of Preferences. Since the Romanian Revolution of 1989, membership of the EC, and its successor the European Union (EU), has been the main goal