This article is from the European Union FAQ, by Roland Siebelink & Bart Schelfhout with numerous contributions by others.
The EU now consists of 15 member states. Its original membership of six was
gradually enlarged as follows:
From 1952 (original ECSC membership):
Belgium (BE);
Germany (DE), the 5 new Ldnder of the former GDR joined in 1991;
France (FR);
Italy (IT);
Luxembourg (LU);
Netherlands (NL);
From 1973 (first enlargement):
Denmark (DK);
Republic of Ireland (IE);
United Kingdom (GB);
[Norwegians rejected membership];
From 1981 (second enlargement):
Greece (GR);
From 1986 (third enlargement):
Portugal (PT);
Spain (ES);
From 1995 (fourth enlargement):
Austria (AT);
Finland (FI);
Sweden (SE);
[Norwegians rejected membership again].
Countries being considered for the fifth enlargement:
Bulgaria (BL);
Cyprus (CY);
Czech Republic (CZ);
Estonia (EE);
Hungary (HU);
Latvia (LV);
Lithuania (LT);
Malta (MT);
Poland (PL);
Romania (RU);
Slovakia (SK);
Slovenia (SL).
Of these, only Malta and Cyprus have been promised that the actual
negotiations for their accession will start six months after finalisation of
the Intergovernmental Conference.[4] In December 1995, the European
Council[5] decided that indidividual assessments of the remaining ten
candidates' prospects as well as a collective assessment of enlargement
should be ready by that time as well, so that membership negotiations with
some of the other countries could start at the same time as those with
Cyprus and Malta.
In preparation for this, all twelve countries are invited to one meeting of
the European Council every year, although it has been made clear that this
does not automatically mean that all countries will be invited as new
candidate members.
Turkey and Morocco have applied for membership in the past, but their
candidacies were rejected. Turkey did finally get its long-awaited customs
union treaty with the EU in 1996.
 
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