Independence movements

History of Northern Ireland's constitutional question since 1998

From the Good Friday Agreement and its border poll mechanism, through the 2022 Assembly election and 2023 Windsor Framework, to Michelle O'Neill's 2024 appointment as First Minister and current polling on Irish unification.

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The Good Friday Agreement, 1998

The Good Friday (Belfast) Agreement was reached on 10 April 1998 between the British and Irish Governments and most of Northern Ireland's political parties.[1] It was put to concurrent referendums: 71.1% of Northern Ireland voters approved it on 22 May 1998, on a turnout of 81.1%, while a simultaneous Republic of Ireland referendum approved related constitutional changes by 94.4% on a 55.6% turnout — together the first all-Ireland poll since 1918.[2][3]

The Agreement establishes that a united Ireland can be brought about only with the concurrent consent of majorities in both Northern Ireland and the Republic of Ireland, voting separately in referendums.[4] The Northern Ireland Act 1998, which implemented the Agreement, gives the UK Secretary of State a discretionary power to call such a "border poll" at any time (subject to a minimum seven-year gap between polls), and a duty to call one if it appears likely that a majority would vote for unification — though neither the Agreement nor the Act defines how that likelihood is to be judged.[5][6]

· Agreement

Good Friday (Belfast) Agreement and referendums, 1998

A peace agreement between the British and Irish Governments and most Northern Ireland parties was overwhelmingly approved in concurrent referendums, establishing the constitutional framework and consent principle still in force today.

The 2022 Assembly election and the DUP boycott

At the Assembly election of 5 May 2022, Sinn Féin won 27 seats, becoming the largest party in the Northern Ireland Assembly for the first time — the first time an Irish nationalist or republican party had done so, entitling it to nominate the First Minister.[7] The Democratic Unionist Party, in protest at the Northern Ireland Protocol's post-Brexit trading arrangements, refused to nominate a deputy First Minister, preventing the Executive from forming and leaving Sinn Féin's Michelle O'Neill unable to take up the post for two years.[8]

· Election

Northern Ireland Assembly election, 2022

Sinn Féin became the Assembly's largest party for the first time, but a DUP boycott prevented the Executive from forming for two years.

The Windsor Framework and the restoration of power-sharing

On 27 February 2023, after two years of negotiations, the UK and the EU announced the Windsor Framework, revising how the Northern Ireland Protocol operates.[9] On 30 January 2024 the DUP endorsed a further UK Government deal on the Framework's operation, ending its boycott and enabling the Assembly and Executive to be restored.[10]

On 3 February 2024, Michelle O'Neill was appointed First Minister of Northern Ireland, becoming the first Irish nationalist to hold the post.[11]

· Agreement

Windsor Framework, 2023

The UK and EU agreed revisions to the Northern Ireland Protocol's operation, later paving the way for the DUP to end its Stormont boycott.

Current polling on Irish unification

A 2026 survey by the Institute of Irish Studies at the University of Liverpool found 35.8% support in Northern Ireland for Irish unification, down from 40.6% in a 2025 survey by the same institute.[12] By contrast, a May 2026 poll found markedly higher support — 63% to 29% in Northern Ireland — when the question framed unification as joining the EU, compared with lower support for plain unification questions.[13]

Analysts have observed that the outcome of any future border poll would likely depend heavily on how the question is framed.[14]

Sources for this page

Each number marks a specific claim. Notes give the source, its locator and how it relates to the claim.

  1. 1.

    Claim: The Good Friday (Belfast) Agreement was reached on 10 April 1998 between the British and Irish Governments and most of Northern Ireland's political parties.

    • 1998 Northern Ireland Good Friday Agreement referendum (Wikipedia) link, Background section. Source record
  2. 2.

    Claim: In a referendum on 22 May 1998, 71.1% of voters in Northern Ireland approved the Good Friday Agreement, on a turnout of 81.1%.

    • 1998 Northern Ireland Good Friday Agreement referendum (Wikipedia) link, Results section. Source record
  3. 3.

    Claim: A simultaneous referendum in the Republic of Ireland approved related constitutional changes by 94.4%, on a turnout of 55.6%; together the two votes were the first all-Ireland poll since 1918.

    • 1998 Northern Ireland Good Friday Agreement referendum (Wikipedia) link, Republic of Ireland results section. Source record
  4. 4.

    Claim: The Agreement provides that a united Ireland can be brought about only with the concurrent consent of majorities in both Northern Ireland and the Republic of Ireland, voting separately.

    • Irish reunification (Institute for Government) link, The principle of consent. Source record
  5. 5.

    Claim: Under the Northern Ireland Act 1998, which implemented the Good Friday Agreement, the Secretary of State for Northern Ireland has a discretionary power to call a "border poll" on Irish unification at any time (subject to a minimum seven-year gap between polls), and a duty to call one if it appears likely that a majority would vote for unification.

    • House of Commons Library, Northern Ireland: border polls (UK Parliament) link, The legal framework. Government perspective or primary official source Source record
  6. 6.

    Claim: Neither the Good Friday Agreement nor the 1998 Act defines how the judgement that unification "appears likely" is to be made; in April 2025 a Northern Ireland Office minister said it would be based on opinion polls, but the Secretary of State, Hilary Benn, subsequently declined to set fixed criteria. Attributed to House of Commons Library, reporting UK Government statements

    • House of Commons Library, Northern Ireland: border polls (UK Parliament) link, Unresolved criteria section. Government perspective or primary official source Source record
  7. 7.

    Claim: At the Assembly election of 5 May 2022, Sinn Féin won 27 seats, becoming the largest party in the Northern Ireland Assembly for the first time and the first time an Irish nationalist or republican party had done so.

    • 2022 Northern Ireland Assembly election (Wikipedia) link, Results section. Source record
  8. 8.

    Claim: The Democratic Unionist Party (DUP) refused to nominate a deputy First Minister after the 2022 election in protest at the Northern Ireland Protocol, preventing the Executive from forming and leaving Michelle O'Neill unable to take up the First Minister post she had become entitled to nominate for.

    • Sinn Féin's Michelle O'Neill elected first ever nationalist First Minister of Northern Ireland (The Irish Times, 3 February 2024) link, article text. Source record
  9. 9.

    Claim: On 27 February 2023, after two years of negotiations, the UK and the EU announced the Windsor Framework, revising how the Northern Ireland Protocol operates.

    • Government deal with the DUP to restore power sharing in Northern Ireland (Institute for Government) link, The Windsor Framework. Source record
    • Windsor Framework (Wikipedia) link, lead section. Source record
  10. 10.

    Claim: On 30 January 2024 the DUP endorsed a UK Government deal on further changes to the Framework's operation, ending its boycott and enabling the restoration of the Assembly and Executive.

    • Government deal with the DUP to restore power sharing in Northern Ireland (Institute for Government) link, The January 2024 deal. Source record
  11. 11.

    Claim: On 3 February 2024, Michelle O'Neill was appointed First Minister of Northern Ireland, becoming the first Irish nationalist to hold the post.

    • Sinn Féin's Michelle O'Neill elected first ever nationalist First Minister of Northern Ireland (The Irish Times, 3 February 2024) link, article text. Source record
  12. 12.

    Claim: A 2026 survey by the Institute of Irish Studies at the University of Liverpool found 35.8% support in Northern Ireland for Irish unification, down from 40.6% in a 2025 survey by the same institute.

    • Poll: support for united Ireland falls in Northern Ireland (UnHerd) link, article text. Source record
  13. 13.

    Claim: A May 2026 poll found markedly higher support for a united Ireland when the question framed unification as joining the EU: 63% in favour to 29% against in Northern Ireland, and 59% to 22% in the Republic of Ireland, compared with lower support for unification questions that do not mention EU membership.

    • New Poll Shows Strong Support for a United Ireland on Both Sides of the Border as Part of the European Union (EU) (Irish Border Poll, 9 May 2026) link, article text. Source record
  14. 14.

    Claim: Analysts have noted that the outcome of any future border poll question would likely depend heavily on how the question itself is framed, with EU-membership framing producing markedly higher support for unification than a plain question about joining the existing Republic of Ireland. Attributed to Analysis accompanying the May 2026 poll

    • New Poll Shows Strong Support for a United Ireland on Both Sides of the Border as Part of the European Union (EU) (Irish Border Poll, 9 May 2026) link, summary of framing effects. Source record

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Printed from https://independenceatlas.com/movements/northern-ireland/history · last substantive update 24 September 2026.