BRUSSELS - The Netherlands voted Wednesday to reject the EU constitution, dealing a second deadly blow to the treaty after a similar vote Sunday in France.
Some 63 percent of Dutch people opposed the text, according to first exit poll, while in France the "no" camp scored nearly 55 percent.
Here are some key dates in the history of the European Union and, in recent years, its constitution.
April 1951: Belgium, France, Germany, Italy, Luxembourg and the Netherlands establish the European Coal and Steel Community (ECSC), creating the foundation for a common market in the coal and steel industry.
March 1957: ECSC members sign the Treaty of Rome establishing the European Economic Community (EEC), with the aim of gradually forming a common agricultural and industrial market.
January 1973: Britain, Denmark and Ireland become members of the EC.
March 1979: European Monetary System enters into force, a first step towards a single European currency.
January 1981: Greece becomes 10th member of the EC.
January 1986: Spain and Portugal become EC members.
April 1987: Turkey formally applies to join the EC.
November 1993: The Treaty of Maastricht comes into force, transforming the EC into the European Union.
January 1995: Austria, Finland and Sweden join the EU.
March 1995: Schengen agreement removing passport checks on EU borders comes into force. Britain and Ireland opt out.
January 1999: Launch of the single European currency, the euro.
December 2000: Nice Treaty agreed enshrining new rules for an enlarged EU, and a timeframe under which new member states' accession is planned.
January 2002: Euro becomes legal tender in 12 EU countries.
December 2002: EU issues formal invitations to 10 mostly ex-communist candidates to join on May 1, 2004.
April 2003: The 10 incoming members sign accession treaties in the shadow of the Acropolis in Athens.
June 2003: A convention chaired by former French president Valery Giscard d'Estaing agrees a draft of a first-ever constitution for the expanding bloc.
May 1, 2004: Ten new countries join the EU in the bloc's biggest-ever expansion: Latvia, Lithuania, Estonia, Poland, the Czech Republic, Slovakia, Hungary, Slovenia, Malta and Cyprus.
June 2004: EU leaders finally agree the new constitution, after a six-month delay due to wrangling over the key issue of power-sharing.
October 2004: The constitution is signed amid fanfare in Rome, recalling the 1957 treaty which started the whole process. It must be ratified over the following two years.
December 2004: EU leaders agree to start accession talks with Turkey in October 2005, so long as certain conditions are fulfilled.
May 29, 2005: France votes against the constitution by 54.67 percent. French President Jacques Chirac "takes note" of voters' "sovereign decision" to reject the EU treaty.
In Brussels the European Union's Luxembourg presidency says the process of ratifying the EU's new constitution must continue.
June 1, 2005: Dutch voters in turn reject the constitution with 63 percent opposing the text, according to exit polls. Prime Minister Jan Peter Balkenende says he is "disappointed" but promises to respect the result.
In Brussels, the Luxembourg presidency again says the ratification process must be allowed to continue.