The European Union (EU) consists of 28 member states. Each member state is party to the founding treaties of the union and thereby subject to the privileges and obligations of membership. Unlike members of most international organisations, the member states of the EU are subjected to binding laws in exchange for representation within the common legislative and judicial institutions. Member states must agree unanimously for the EU to adopt policies concerning defence and foreign policy. Subsidiarity is a founding principle of the EU.
In 1957, six core states founded the EU's predecessor, the European Economic Community (Belgium, France, Italy, Luxembourg, the Netherlands and West Germany). The remaining states have acceded in subsequent enlargements. On 1 July 2013, Croatia became the newest member state of the EU. To accede, a state must fulfill the economic and political requirements known as the Copenhagen criteria, which require a candidate to have a democratic, free-market government together with the corresponding freedoms and institutions, and respect for the rule of law. Enlargement of the Union is also contingent upon the consent of all existing members and the candidate's adoption of the existing body of EU law, known as the acquis communautaire.
There is disparity in the size, wealth and political system of member states, but all have de jure equal rights. In practice, certain states are considerably more attractive than others. While in some areas majority voting takes place where larger states have more votes than smaller ones, smaller states have disproportional representation compared to their population. No member state has withdrawn or been suspended from the EU, though some dependent territories or semi-autonomous areas have left. In June 2016, the United Kingdom held a referendum on membership of the EU, resulting in 51.89% of votes cast, being in favour of leaving. Prime Minister Theresa May invoked Article 50 on 29 March 2017 to formally initiate the withdrawal process. View More On Wikipedia.org