People & Histories
2016–2023

Brexit and the Irish border

The UK votes to leave the EU, turning the open Irish border into the hardest problem of the negotiations.

  • Results and turnout at the EU referendum — The Electoral Commission (UK) (2016)
  • The Windsor Framework — UK Government and European Commission (2023)
  • The Belfast Agreement (Good Friday Agreement) — Governments of the United Kingdom and Ireland, with Northern Ireland parties (1998)

Well established europepartitionpeace

Part of the story of Ireland and Northern Ireland.

In the June 2016 referendum the UK as a whole voted to leave the EU, but Northern Ireland voted 55.8% to remain.

  • Results and turnout at the EU referendum — The Electoral Commission (UK) (2016)
Since the Good Friday Agreement and the EU single market, the 500-kilometre border had become almost invisible, crossed daily by commuters, farmers and goods. Leaving the EU’s customs union and single market meant checks had to happen somewhere.
  • The Belfast Agreement (Good Friday Agreement) — Governments of the United Kingdom and Ireland, with Northern Ireland parties (1998)
  • Northern Ireland — Encyclopaedia Britannica, Encyclopaedia Britannica

After years of negotiation, the Northern Ireland Protocol, in force from 1 January 2021, kept Northern Ireland aligned with EU rules for goods, placing checks on goods coming from Great Britain instead of at the land border. Unionist anger led to the collapse of Stormont, and in February 2023 the UK and EU agreed the Windsor Framework to ease the checks. Power-sharing returned in February 2024.

  • The Windsor Framework — UK Government and European Commission (2023)
  • Northern Ireland — Encyclopaedia Britannica, Encyclopaedia Britannica

How it's seen
Irish government and most nationalists

Any border infrastructure would threaten the peace and the all-island economy built since 1998; the Protocol and Windsor Framework are the price of protecting the Good Friday Agreement.

  • The Windsor Framework — UK Government and European Commission (2023)
  • The Belfast Agreement (Good Friday Agreement) — Governments of the United Kingdom and Ireland, with Northern Ireland parties (1998)

Many unionists

The "Irish Sea border" for goods treats Northern Ireland differently from the rest of the UK and weakens the Union; the DUP's opposition led it to boycott Stormont from 2022 to 2024.

  • The Windsor Framework — UK Government and European Commission (2023)
  • Northern Ireland — Encyclopaedia Britannica, Encyclopaedia Britannica

Northern Ireland's middle ground

Many in the cross-community centre, and many businesses, argue the Windsor Framework has given Northern Ireland a unique advantage, access to both the UK and EU markets, and that the priority should be making it work rather than reopening the fight.

Why it matters today

Ireland

Brexit put the island's only land border back at the centre of politics, revived talk of Irish unity, and unsettled unionists who felt the solution separated them from Britain. Many people in the Republic saw it as a test of whether Europe would stand by a small member state, and it did.

Northern Ireland

Northern Ireland voted 55.8% to Remain and then became the hardest problem of Brexit. The Protocol and the Windsor Framework keep it inside EU rules for goods, with checks on some goods from Britain. Many nationalists and businesses see dual market access as an advantage; many unionists feel cut off from the rest of the UK, and the DUP boycotted Stormont from 2022 to 2024 over it.