enlargement of the European Union

The European Union (EU) was created by six founding states in 1957 (following the earlier establishment by the same six states of the European Coal and Steel Community in 1952) and has grown to 27 member states. There have been five enlargements, with the largest occurring on May 1, 2004, when 10 new member states joined, and the most recent on January 1, 2007, when Bulgaria and Romania joined.
See more at Wikipedia.org...