How did Brexit happen?

From membership to separation, here are the key moments that have led to the UK’s divorce from the European Union


The European Economic Community (EEC), also known as the Common Market, is formed. The EEC is made up of Belgium, France, Italy, Luxembourg, the Netherlands and West Germany, under the Treaty of Rome.


The European Free Trade Association is created as a rival to the EEC. It’s comprised of Austria, Denmark, Norway, Portugal, Sweden, Switzerland and the UK.


The UK submits an application to join the EEC, however, the application is rejected in 1963.


The UK submits two more applications to join the EEC, which are rejected. However, in 1973 the country is granted entry into the EEC along with Denmark and Ireland.


After just two years of membership the UK holds a referendum to decide whether or not to stay in the EEC. The vote resulted in a decision to remain, with 67.2 per cent for and 32.8 per cent against.


New member Greece joins the EEC.


Prime Minister Margaret Thatcher organises a rebate on the UK’s contribution to the EEC.


The UK refuses to sign The Schengen Treaty to join in a borderless zone across member states.


New members Portugal and Spain join the EEC.


Under the new Maastricht Treaty, signed by UK Prime Minister John Major, the European Union (EU) is formed to offer a single currency and the coordination of social and security policy, in which EEC members are enrolled.


New members Austria, Finland and Sweden join the EU.


Security and employment policies are strengthened by the signing of The Treaty of Amsterdam by member states.


The Treaty of Nice is signed by the 15 member states of the EU to prepare for the next large intake of members to strengthen the institution.


New members Cyprus, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia and Slovenia join the EU.


New members Bulgaria and Romania join the EU. The Treaty of Lisbon is signed by UK Prime Minister Gordon Brown to extend the powers of the European parliament.


New member Croatia joins the EU.


Britain carries out a nationwide referendum to decide its membership of the EU. The result is 5.1.9 per cent to leave, 48.1 to remain.

Nov–Dec 2018

The UK government finally reaches a Brexit deal with the EU, however the deal is rejected by a UK parliament vote.

Jan-Dec 2019

After renegotiations between the UK government and the EU, an amended deal is presented and again rejected in a vote by the UK parliament. Boris Johnson wins the Tory leadership election in July, then a general election in December. A massive Tory majority means he is easily able to push his Withdrawal bill through parliament. 

31 Jan 2020

The UK formally leaves the European Union.

This article was originally published in How It Works issue 123

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