European Union Fast Facts

European Union flag at the Mirador de San Vicente in Rio Madrid, Spain, April 2011. (Photo by Cristina Arias/Cover/Getty Images), April 2011

(CNN)Here is some background information about the European Union.

About the European Union:
The European Union is an international organization made up of 28 European countries.
It governs common economic, social and security policies of its member states.
    According to the EU website, the objectives of the EU are to establish European citizenship, ensure freedom, justice and security, promote economic and social progress, and assert Europe's role in the world.
    Membership is open to any country with a democratic government, a good human rights record, and sound economic policies.
    The member states delegate sovereignty to the EU institutions to represent the interests of the European Union as a whole.
    Decisions and procedures stem from treaties ratified by the member states.
    The capital of the European Union is Brussels, Belgium.
    The EU is run by five main bodies: European Parliament, Council of the Union, European Commission, Court of Justice, and the Court of Auditors.
    An estimated 508.2 million people lived within the European Union in 2015.
    The United States is the EU's main trading partner.
    The Treaty of Lisbon amends the Treaty on European Union to explicitly recognize for the first time the member states' right to withdraw from the union. (Article 50, amended TEU)
    - Any member state may decide to withdraw from the Union in accordance with its own constitutional requirements.
    - A member state which decides to withdraw shall notify the European Council of its intention. In the light of the guidelines provided by the European Council, the Union shall negotiate and conclude an agreement with that State, setting out the arrangements for its withdrawal, taking account of the framework for its future relationship with the Union.
    Timeline:
    1957 -
    The European Economic Community (EEC) is created. The member countries are Belgium, France, Italy, Luxembourg, the Netherlands, and West Germany. The group aims to remove trade barriers and form a common market.
    1973 - Denmark, Ireland, and the United Kingdom become member countries.
    1981 - Greece becomes a member.
    1985 - Spain and Portugal become members.
    June 14, 1985 - Five of the 10 member states sign the Schengen Agreement, which eventually opens borders of agreeing member states, doing away with border controls. As of 2016, 26 countries belong to the Schengen Area.
    February 7, 1992 - The Treaty on the European Union is signed in Maastricht (Netherlands) by leaders of the member states.
    November 1, 1993 - The Maastricht Treaty enters into force.
    1993 - The EC members at the time (Belgium, France, Germany, Italy, Greece, Spain, UK, Luxembourg, the Netherlands, Denmark, Ireland, and Portugal) extend their cooperation into the areas of justice and home affairs and a common foreign and security policy.
    January 1, 1995 - Austria, Finland, and Sweden join the EU.
    April 30, 2004 - A ceremony is held in Dublin, Ireland, marking the expansion of the EU from 15 to 25 members. The new members are Poland, the Czech Republic, Slovakia, Cyprus, Estonia, Hungary, Latvia, Lithuania, Malta, and Slovenia.
    June 2004 - The member countries approve the text of the EU Constitution. It is signed by all the members in October 2004.
    May 29, 2005 - The people of France (and its territories) vote against the European Union constitution in a referendum. (No = 54.87%/Yes = 45.13%)
    June 1, 2005 - The Netherlands votes against the constitution in a referendum. All 27 members of the EU must pass the constitution for it to take effect. Either a national parliament can approve it or in some countries, the citizens vote on a referendum.
    June 23, 2007 - European Union leaders in Brussels agree on an outline of a treaty that would replace the EU constitution rejected by French and Dutch voters two years ago.
    June 19, 2008 - The European Union decides to lift diplomatic sanctions imposed on Cuba.
    November 19, 2009 - Herman Van Rompuy, the Belgian Prime Minister, becomes the first president of the European Council under the Treaty of Lisbon. Catherine Ashton of the UK will be the first foreign minister.
    December 1, 2009 - The Treaty of Lisbon comes into force, having been ratified by all European Union member states. It amends the Maastricht Treaty of 1992 and the Rome Treaty of 1957.
    October 12, 2012 - Is awarded the Nobel Peace Prize for contributing to the advancement of peace, democracy and human rights in Europe.
    July 1, 2013 - Croatia joins the EU as its 28th member.
    April 1, 2014 - The European Union launches military operations to restore stability to the Central African Republic.
    March 2015 - Iceland withdraws its request to be considered as a candidate for membership.
    March 18, 2016 - The EU and Turkey reach an agreement on how to deal with a flood of Syrian refugees. The agreement stipulates that all migrants entering Greece from Turkey will be returned to Turkey. For every Syrian returned to Turkey from Greece, another Syrian will be resettled to the EU.
    Presidencies of the Council of the European Union until 2020:
    Netherlands: January-June 2016
    Slovakia: July-December 2016
    Malta: January-June 2017
    United Kingdom: July-December 2017
    Estonia: January-June 2018
    Bulgaria: July-December 2018
    Austria: January-June 2019
    Romania: July-December 2019
    Finland: January-June 2020
    Current Members:
    (Founding members in bold)
    Austria
    Belgium
    Bulgaria
    Croatia
    Cyprus
    Czech Republic
    Denmark
    Estonia
    Finland
    France
    Germany
    Greece
    Hungary
    Ireland
    Italy
    Latvia
    Lithuania
    Luxembourg
    Malta
    Netherlands
    Poland
    Portugal
    Romania
    Slovakia
    Slovenia
    Spain
    Sweden
    United Kingdom - voted to leave June 24, 2016.
    Candidate Countries:
    Albania
    Macedonia
    Montenegro
    Serbia
    Turkey
    Applicant Countries:
    Bosnia and Herzegovina
    Kosovo