This is a timeline of European Union history and its previous development.
European Coal and Steel Community
- 1950s
- 1952
- 1953
- 1954
- 1955
- 1956
- 1957
European Economic Community
- 1960s
- 1960
- 1961
- 1962
- 1963
- 1964
- 1965
- 1966
European Communities
- 1970s
- 1970
- 1971
- 1972
- 1973
- 1974
- 1975
- 1976
- 1977
- 1978
- 1979
- 1980s
- 1980
- 1981
- 1982
- 1983
- 1984
- 1985
- 1986
- 1987
- 1988
- 1989
European Union
- 1948 – Treaty of Brussels establishing the Western Union;
- 1948 – Formation of the International Authority for the Ruhr
- 1949 – Treaty of London establishing the Council of Europe
- 1950 – Schuman Declaration proposes pooling French and German markets for coal and steel
- 1951 – Treaty of Paris creates the European Coal and Steel Community (ECSC)
- 1954 – Paris Agreements; Western Union transformed into Western European Union
- 1957 – Treaty of Rome creates European Economic Community (by "The Six": Belgium, France, Italy, Luxembourg, the Netherlands and West Germany)
- 1963 – Ankara Agreement initiated a three-step process toward creating a Customs Union which would help secure Turkey's full membership in the EEC.
- 1963 – Charles de Gaulle vetoes UK entry
- 1967 – ECSC, EEC and Euratom merged
- 1973 – Accession of Denmark, Ireland and the UK
- 1979 – First direct elections to Parliament
- 1981 – Accession of Greece
- 1985 – Delors Commission, Greenland leaves Community.
- 1986 – Single European Act; Accession of Portugal and Spain; flag adopted
- 1989 – The fall of the Iron Curtain in Eastern Europe
- 1992 – Maastricht Treaty formally called the Treaty on European Union - The European Union is born and Euro was introduced as the fellow currency (Denmark and the UK are not included in the EMU (European Monetary Union)).
- 1993 – Copenhagen criteria defined
- 1995 – Accession of Austria, Finland and Sweden
- 1997 – Treaty of Amsterdam
- 1999 – Fraud in the Commission results in resignation
- 1999 - The Euro as an 'accounting currency' officially replaces twelve national currencies
- 2002 – Euro banknotes and coins physically replace the twelve national currencies
- 2003 – Treaty of Nice
- 2004 – Accession of ten countries (Cyprus, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia, Slovenia); signing of Constitution
- 2005 – France and the Netherlands reject the Constitution after own internal referendums (for France it was a binding one only)
- 2005 – Accession negotiations for full membership started with Croatia and Turkey.
- 2007 – Accession of Bulgaria and Romania
- 2009 – Lisbon Treaty abolishes the three pillars of the European Union
- 2013 – Accession of Croatia
- 2016 – UK holds a Membership Referendum and votes to leave the European Union
- 2017 – Negotiations between UK and the EU officially started in June 2017
- 2017 – Start of Brexit: On 29 March 2017, the Government of the United Kingdom invoked Article 50 of the Treaty on European Union. The UK was due to leave the EU on 29 March 2019 at 11 p.m. GMT, when the period for negotiating a withdrawal agreement was set to end
- 2020 – UK leaves the EU after the Brexit withdrawal agreement takes effect on 31 January 2020 at 11 p.m. GMT
- 2022 – Granted full candidacy status with Ukraine and Moldova.
- 2024 – Accession negotiations for full membership started with Moldova and Ukraine.
Since the end of World War II, sovereign European countries have entered into treaties and thereby co-operated and harmonised policies (or pooled sovereignty) in an increasing number of areas, in the European integration project or the construction of Europe (French: la construction européenne). The following timeline outlines the legal inception of the European Union (EU)—the principal framework for this unification. The EU inherited many of its present responsibilities from the European Communities (EC), which were founded in the 1950s in the spirit of the Schuman Declaration.
Although not EU treaties per se, these treaties affected the development of the EU defence arm, a main part of the CFSP. The Franco-British alliance established by the Dunkirk Treaty was de facto superseded by WU. The CFSP pillar was bolstered by some of the security structures that had been established within the remit of the 1955 Modified Brussels Treaty (MBT). The Brussels Treaty was terminated in 2011, consequently dissolving the WEU, as the mutual defence clause that the Lisbon Treaty provided for EU was considered to render the WEU superfluous. The EU thus de facto superseded the WEU.
Between the EU's founding in 1993 and consolidation in 2009, the union consisted of three pillars, the first of which were the European Communities. The other two pillars consisted of additional areas of cooperation that had been added to the EU's remit.