United Kingdom

Brexit (2020)

21st Century · 2000 – present

Brexit is the withdrawal of the United Kingdom from the European Union. In a referendum on 23 June 2016, 51.9 per cent of voters chose to leave and 48.1 per cent chose to remain. The UK formally left the EU on 31 January 2020, and a transition period during which most EU rules still applied ended on 31 December 2020. It was the first time a member state had left the Union.

The UK had joined the European Communities in 1973 and had long been a member with some distinct terms, staying outside the euro and the Schengen travel area. Debates over sovereignty, immigration, trade and the economy shaped the vote, and the following years were marked by long negotiations and political upheaval. The terms of the exit were set out in a withdrawal agreement and a trade deal, and their effects on trade, on Northern Ireland and on politics are still debated.

Things happened, and the rest is history

The UK joins the European Communities
Event
What happened
After two earlier applications were vetoed by French president Charles de Gaulle, the UK signs the treaty of accession in Brussels in January 1972. It joins the European Communities on 1 January 1973 under Prime Minister Edward Heath, together with Ireland and Denmark.
The rest is history
Membership was contested from the start. In 1975 the Labour government held a referendum on whether to stay, after renegotiating terms, and about two thirds of voters chose to remain. The question of the UK's place in Europe remained a recurring source of division, especially within the Conservative Party. The 1975 vote was the first nationwide referendum in UK history.
Sources
1. BookYoung, Hugo. This Blessed Plot: Britain and Europe from Churchill to Blair. London: Macmillan, 1998.
2. BookGeorge, Stephen. An Awkward Partner: Britain in the European Community. Oxford: Oxford University Press, 1990.
The Maastricht Treaty and the opt-outs
Event
What happened
In 1992 EU leaders sign the Maastricht Treaty, which creates the European Union and sets a path to a single currency. Prime Minister John Major negotiates an opt-out from the euro and from the Social Chapter. Parliament ratifies the treaty in 1993 after a bitter fight among Conservative MPs.
The rest is history
The ratification fight deepened Eurosceptic feeling in the Conservative Party, and the UK Independence Party was founded in 1993. The UK later also stayed outside the Schengen area. These opt-outs meant that the UK was already a partial member before 2016, which shaped later arguments about how far it needed to leave.
Sources
1. BookGowland, David, Arthur Turner, and Alex Wright. Britain and European Integration since 1945: On the Sidelines. London: Routledge, 2010.
2. BookYoung, Hugo. This Blessed Plot: Britain and Europe from Churchill to Blair. London: Macmillan, 1998.
The rise of UKIP and the Bloomberg speech
Event
What happened
The UK Independence Party grows through the 2000s and wins the most UK seats in the 2014 European Parliament election. On 23 January 2013 Prime Minister David Cameron promises in a speech to renegotiate the UK's membership and then hold an in-or-out referendum. The Conservatives win the 2015 general election with a manifesto commitment to hold one.
The rest is history
Historians point to several pressures behind the pledge, including party divisions and competition from UKIP, and they debate how much weight each deserves. The European Union Referendum Act 2015 set the vote. In February 2016 Cameron announced a renegotiated deal and named 23 June as the date.
Sources
1. BookShipman, Tim. All Out War: The Full Story of How Brexit Sank Britain's Political Class. London: William Collins, 2016.
2. BookFord, Robert, and Matthew Goodwin. Revolt on the Right: Explaining Public Support for the Radical Right in Britain. London: Routledge, 2014.
The 2016 referendum
Event
What happened
On 23 June 2016 about 72 per cent of eligible voters take part in the EU referendum. Leave wins with 51.9 per cent to Remain's 48.1 per cent. England and Wales vote to leave, while Scotland and Northern Ireland vote to remain. Cameron resigns the next day.
The rest is history
Theresa May became prime minister in July 2016. Researchers have linked the result to factors such as age, education, regional economic decline and attitudes to immigration and sovereignty, though the weight of each is debated. The result also reopened questions about Scottish independence and the Irish border.
Sources
1. PrimaryElectoral Commission. Report on the 23 June 2016 referendum on the UK's membership of the European Union. London, 2016.
2. BookClarke, Harold D., Matthew Goodwin, and Paul Whiteley. Brexit: Why Britain Voted to Leave the European Union. Cambridge: Cambridge University Press, 2017.
Article 50 and the failed withdrawal deal
Event
What happened
On 29 March 2017 Theresa May triggers Article 50 of the Treaty on European Union, starting a two-year countdown to exit. A withdrawal agreement is reached with the EU in November 2018. The House of Commons rejects it three times in early 2019, and the deadline is extended more than once.
The rest is history
The main sticking point was the Irish border backstop, meant to avoid checks between Northern Ireland and the Republic of Ireland. May announced her resignation in May 2019, and Boris Johnson succeeded her in July. Parliament was deeply divided, and the extensions pushed the exit date to the start of 2020.
Sources
1. BookBarnard, Catherine, and Steve Peers, eds. European Union Law. Oxford: Oxford University Press, 2017.
2. BookShipman, Tim. Fall Out: A Year of Political Mayhem. London: William Collins, 2017.
The 2019 general election and the new withdrawal deal
Event
What happened
In October 2019 Boris Johnson agrees a revised withdrawal deal with the EU, replacing the backstop with a Northern Ireland Protocol. Parliament does not pass it in time, and an early general election is held on 12 December 2019. The Conservatives win an 80-seat majority on the slogan 'Get Brexit Done'.
The rest is history
The new majority passed the withdrawal agreement law in January 2020. The UK left the EU at 11 pm GMT on 31 January 2020, with a transition period running to the end of the year. The Northern Ireland Protocol later became a continuing source of dispute.
Sources
1. PrimaryAgreement on the withdrawal of the United Kingdom of Great Britain and Northern Ireland from the European Union and the European Atomic Energy Community. Treaty text, Official Journal of the European Union, 2019/2020.
2. BookSeldon, Anthony, with Raymond Newell. Johnson at 10: The Inside Story. London: Atlantic Books, 2023.
Exit day and the Trade and Cooperation Agreement
Event
What happened
The UK leaves the EU on 31 January 2020. During 2020 the two sides negotiate a trade deal, which is agreed on 24 December 2020. It takes provisional effect on 1 January 2021, when the UK leaves the single market and customs union.
The rest is history
The agreement avoided tariffs and quotas on goods but introduced new customs and regulatory checks. Services were covered less fully. Economists have since studied its effects on trade and growth, and estimates and their causes remain debated.
Sources
1. PrimaryTrade and Cooperation Agreement between the European Union and the United Kingdom. Treaty, signed 30 December 2020. Official Journal of the European Union, L 444.
2. BookMenon, Anand, ed. Brexit and Beyond. London: UK in a Changing Europe, 2021.
The Northern Ireland Protocol and the Windsor Framework
Event
What happened
Under the 2019 withdrawal deal, Northern Ireland stays aligned with some EU rules so that no hard border returns on the island of Ireland. This creates checks on some goods moving from Great Britain. In February 2023 the UK and EU agree the Windsor Framework to ease those checks.
The rest is history
Unionist parties objected that the Protocol set Northern Ireland apart from the rest of the UK, and the devolved government at Stormont was suspended for a long period from 2022. It resumed in early 2024. The arrangements show how the Irish border became one of the hardest issues of Brexit.
Sources
1. PrimaryWindsor Framework. Joint UK-EU political agreement, 27 February 2023.
2. BookTonge, Jonathan, Stephen Farrington, and others. Brexit and Northern Ireland. London: Bloomsbury, 2022.
The claim of 350 million pounds a week for the NHS
Popular belief
The legend
A red campaign bus in 2016 carries the slogan that the UK sends the EU 350 million pounds a week, and that this money could instead fund the National Health Service. Many people repeat it as the amount saved by leaving.
The rest is history
The UK Statistics Authority said the figure was misleading, since it ignored the UK rebate and money the EU spent in the UK. The net contribution was lower, in the region of 100 to 200 million pounds a week depending on the year. The figure was widely debated during and after the campaign. The Statistics Authority's letter was published in September 2016.
Sources
1. PrimaryUK Statistics Authority. Letter from Sir Andrew Dilnot to Sir Ivan Rogers and others on the use of official statistics on the EU contribution. London, 2016.
2. BookClarke, Harold D., Matthew Goodwin, and Paul Whiteley. Brexit: Why Britain Voted to Leave the European Union. Cambridge: Cambridge University Press, 2017.
Brexit was voted for only by the old and the English
Popular belief
The legend
A common claim is that Brexit was a vote of older and English voters, with the young and the rest of the UK all opposed.
The rest is history
There is truth in the pattern. Older voters backed Leave more than younger ones, and England and Wales voted Leave while Scotland and Northern Ireland voted Remain. But the divide was partial. Many younger people voted Leave and many older people voted Remain, and education, place and attitudes mattered as much as age. Survey analyses after the vote found a strong link with education level, and Leave won large majorities in many areas of England outside London.
Sources
1. BookClarke, Harold D., Matthew Goodwin, and Paul Whiteley. Brexit: Why Britain Voted to Leave the European Union. Cambridge: Cambridge University Press, 2017.
2. ArticleGoodwin, Matthew J., and Oliver Heath. "The 2016 Referendum, Brexit and the Left Behind." Political Quarterly 87, no. 3 (2016): 323-332.
The Brexit date was set by a single day
Popular belief
The legend
Many people recall Brexit as happening on a single day, either the vote on 23 June 2016 or an exit day when everything changed.
The rest is history
The process was spread over years. The 2016 vote was advisory in law, not binding. The legal exit followed on 31 January 2020, but most rules stayed in place through 2020. The real practical break came on 1 January 2021, when the transition ended and the trade deal took effect. Some arrangements, such as those for Northern Ireland, were revised again in 2023.
Sources
1. PrimaryEuropean Union (Withdrawal Agreement) Act 2020. Act of the UK Parliament, 2020.
2. BookMenon, Anand, ed. Brexit and Beyond. London: UK in a Changing Europe, 2021.
The Brexit bus and the 'Project Fear' stories
Popular belief
The legend
Each side is said to have told lies. Leave supporters say the Remain campaign invented 'Project Fear', and that every warning of economic damage proved false.
The rest is history
The Remain campaign did make dire forecasts, including that a vote to leave would trigger an immediate recession, which did not occur. Later economic studies nonetheless estimated that trade and investment were affected over several years, though the size is disputed. The Office for Budget Responsibility estimated in 2024 that Brexit would reduce long-run productivity by about 4 per cent compared with staying in.
Sources
1. PrimaryOffice for Budget Responsibility. Economic and Fiscal Outlook. London, 2024.
2. BookMenon, Anand, ed. Brexit and Beyond. London: UK in a Changing Europe, 2021.

← Back to the outline

Things happened, and the rest is history

The UK joins the European Communities

The Maastricht Treaty and the opt-outs

The rise of UKIP and the Bloomberg speech

The 2016 referendum

Article 50 and the failed withdrawal deal

The 2019 general election and the new withdrawal deal

Exit day and the Trade and Cooperation Agreement

The Northern Ireland Protocol and the Windsor Framework

The claim of 350 million pounds a week for the NHS

Brexit was voted for only by the old and the English

The Brexit date was set by a single day

The Brexit bus and the 'Project Fear' stories