The European Union: A brief history
Britain goes to the polls on Thursday, June 23 in referendum to decide whether the nation should remain in the European Union.
Voters will be asked: "Should the United Kingdom remain a member of the European Union or leave the European Union?"
There will be a choice of two answers - "Remain a member of the European Union" and "Leave the European Union".
British, Irish and Commonwealth citizens over 18 who are resident in the UK, along with UK nationals living abroad who have been on the electoral register in the UK in the past 15 years, will be eligible to vote.
Pledged to renegotiate Britain's membership terms
Britain last had a referendum on Europe more than 40 years ago. It took place in 1975, two years after the UK joined the European Economic Community (which evolved into the EU) under Tory prime minister Edward Heath.
Labour was returned to power under Harold Wilson the following year and pledged to renegotiate Britain's membership terms. This 'new deal' was the basis of the 1975 referendum, in which UK citizens voted to remain in Europe by a majority of 2-1.
Since then, the EU has grown from nine countries to 28. Member states are: 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 and the United Kingdom.
The EU has evolved from a common market to a political and monetary union comprising four key institutions: The European Commission, the European Parliament, the European Council and the Court of Justice.
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