Moving Past the Troubles: The Future of Northern Ireland Peace

Moving Past the Troubles: The Future of Northern Ireland Peace

The Good Friday Agreement has dampened sectarian conflict and brought stability to Northern Ireland, but the peace deal has been challenged by Brexit-related border tensions that have thrown the region’s hard-won gains into doubt.
A peace mural adorns a building in a loyalist neighborhood of Belfast.
A peace mural adorns a building in a loyalist neighborhood of Belfast. Charles McQuillan/Getty Images
  • Northern Ireland, which is part of the United Kingdom (UK), suffered decades of violence known as the Troubles, a conflict largely between pro-UK Protestants and pro-secession Catholics.
  • The 1998 Good Friday Agreement achieved compromise by creating a new power-sharing government, facilitating disarmament, and abolishing border checks between Northern Ireland and the Republic of Ireland.
  • Brexit, with its novel trade and border arrangements, has stoked disillusionment among some Protestants, sparking worries over renewed conflict.


Northern Ireland, a long-contested region of the United Kingdom (UK), experienced decades of conflict between the late 1960s and the late 1990s that killed more than 3,500 people. The era, known as the Troubles, largely pitted the historically dominant Protestants against the Catholic minority. A peace deal struck in April 1998 created a power-sharing government that included political forces aligned with armed groups.

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More than twenty-five years later, most of the Belfast Agreement—usually referred to as the Good Friday Agreement—has been implemented. Although paramilitary groups still exist, they have mostly disarmed, and to a large extent violence between the two sides has ceased. However, controversy over the UK’s departure from the European Union (EU) in 2020, known as Brexit, has complicated Northern Ireland’s border arrangements. The so-called Northern Ireland Protocol, which implements new border checks for goods coming from Great Britain, has sparked fears over the possibility that renewed sectarianism could undermine the progress achieved by the Good Friday Agreement. Meanwhile, the republican Sinn Fein political party has taken leadership of the Northern Ireland government for the first time in early 2024, reviving the debate over the potential for a referendum on unification with the Republic of Ireland.

What has driven the conflict in Northern Ireland?

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Northern Ireland’s modern period of conflict started in the late 1960s and lasted more than three decades. What started as a civil rights movement—Catholics protesting what they saw as discrimination by Northern Ireland’s Protestant-dominated government—deteriorated into violence, with the involvement of paramilitary groups on both sides and the arrival in 1969 of the British Army.

The conflict involved mostly Protestant loyalists, who wanted to remain part of the UK, against mostly Catholic republicans, who wished to unite with the Republic of Ireland. Protestant unionists and Catholic nationalists shared their respective communities’ goals but tended to eschew violence.

What is the Good Friday Agreement?

Reached in 1998, the Good Friday Agreement provided a framework for political settlement in Northern Ireland centered on power-sharing between unionists and nationalists. It was signed by the British and Irish governments, as well as four of the major political parties in Northern Ireland: Sinn Fein, the Ulster Unionist Party, the Social Democratic and Labour Party, and the Alliance Party. Among major parties, only the Democratic Unionist Party (DUP) abstained. While the agreement confirmed that Northern Ireland is a part of the UK, it stipulates that Ireland could be united if that was supported in a vote by majorities in both Northern Ireland and the Republic of Ireland.

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A map of the United Kingdom and Ireland

The agreement called for the devolution of authority over certain policy areas from the UK Parliament to a newly created assembly in Belfast, and it paved the way for paramilitary groups to abandon their weapons and join the political process. It has contributed to a sharp reduction in violence, and the annual conflict-related death toll, which peaked at 480 in 1972, has dropped to the single digits in recent years.

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What is the governing structure of Northern Ireland?

The government in Northern Ireland is composed of two main bodies, both based at the Stormont Estate in Belfast, the capital.

Legislature. A popularly elected, ninety-member assembly legislates on matters such as health, education, and agriculture. The assembly requires support from both unionists and nationalists to make important decisions, ensuring that neither can dominate.

Executive. A cabinet-like executive administers the government. It is chaired by a first minister and a deputy first minister, one from each main tradition. For most of the deal’s history, the first minister was always a unionist and the deputy first minister a nationalist or republican. However, in 2024 Sinn Fein’s Michelle O’Neill became first minister, the first Irish nationalist to lead Northern Ireland’s government since the state’s modern founding in 1921.

Has the Good Friday Agreement been successful?

Distrust among the factions persisted for years after the accord. Political jockeying over devolution—the transfer of police, judicial, and other powers from London to Belfast—and the decommissioning of paramilitary groups’ weapons hindered implementation of the Good Friday Agreement. While London devolved local powers in late 1999, political turmoil in Northern Ireland prompted it to reimpose direct rule in 2000 and again in 2002. London only restored the devolved government in 2007, with the breakthrough St. Andrews Agreement, signed by the UK and Irish governments and Northern Ireland’s main parties. By then, the DUP was the largest unionist party and Sinn Fein the largest among nationalists and republicans.

Another milestone came in 2010 with the Hillsborough Agreement, in which Sinn Fein and the DUP finally agreed on terms for the devolution of policing and justice functions, as well as a roadmap for managing sectarian parades. By the mid-2010s, the political institutions envisioned in the Good Friday Agreement were generally functioning well, as parties with starkly differing views served together in government.

What is the status of Northern Ireland’s government?

The relative political stability in Belfast began to unravel in 2017, when an energy scandal precipitated the resignation of Sinn Fein’s Martin McGuinness as deputy first minister. This caused the executive’s collapse and led to fresh elections for the assembly in March 2017. The DUP remained the largest single party, but its advantage over Sinn Fein fell to just one seat, a result indicative of Northern Ireland’s demographic shifts: the 2021 census showed that those of Catholic heritage outnumbered those of Protestant upbringing for the first time, at 46 percent to 44 percent of the population, respectively. The impasse also highlighted deep divisions over Brexit, which the unionist DUP favored and Sinn Fein (along with other major parties) opposed.

The DUP and Sinn Fein were unable to resolve their differences for nearly three years. Northern Ireland was left without a local government until January 2020, when the two parties made a deal to reopen Stormont. In a major compromise, the deal included an agreement to promote the local Irish and Ulster Scots languages. It also marked the first time that the devolved government was led by two women, First Minister Arlene Foster (DUP) and Deputy First Minister Michelle O’Neill (Sinn Fein). 

However, cooperation was short-lived. Foster stepped down in April 2021 after facing pressure over new trade checks on goods traveling to Northern Ireland from the rest of the UK as a consequence of the Northern Ireland Protocol. She was replaced by the DUP’s Paul Givan, who in turn resigned in February 2022 in protest against the protocol. May 2022 elections made Sinn Fein the largest party in the assembly for the first time, but the DUP’s continued boycott kept the government out of commission into 2024. In January 2024, the UK government reached a deal with the DUP to update the protocol and pave the way for a restored government under Sinn Fein’s O’Neill as first minister.

What other challenges remain?

Northern Ireland continues to struggle to provide basic services and address sectarian divisions. Health services fell into crisis after the breakdown of local government and were further stressed by the COVID-19 pandemic. Nurses and other health-care workers have repeatedly gone on strike to protest salaries that have fallen below those in the rest of the UK while a cost of living crisis is contributing to rising energy and food insecurity. Additionally, the loss of EU funding due to Brexit, combined with the defunct Stormont executive, has slashed funding for many important social programs.

Meanwhile, sectarian divisions remain prominent. Less than 10 percent of students in Northern Ireland attend religiously integrated schools, or those not primarily associated with a single faith. Social interaction between the two main religious communities remains limited. Dozens of so-called peace walls divide Protestant and Catholic neighborhoods.

Other long-standing issues continue to cause friction. Parades and marches—held mainly but not exclusively by Protestant groups—often have heavily sectarian undertones. The same is true of flags and emblems, displayed by all sides on lampposts and buildings. Moreover, Northern Ireland’s leaders have never developed a comprehensive approach to the legacy of past violence, as some other postconflict societies have. Efforts to prosecute those responsible for killings and to pursue other initiatives have been uneven, which analysts say has hindered reconciliation.

These issues—parades, flags, and the legacy of the past—were the subject of 2013 negotiations chaired by Richard Haass, president of the Council on Foreign Relations, and Meghan L. O’Sullivan, a professor at the Harvard Kennedy School and now on CFR’s Board of Directors. The talks, which involved the five main political parties, did not produce an agreement, though many of the proposals—including establishing a historical investigations unit to look into unsolved deaths during the conflict and a commission to help victims get information about relatives’ deaths—formed a large part of the Stormont House Agreement, reached in 2014. The UK government pledged to implement many of these measures as part of the January 2020 accord to restore Stormont, but progress has lagged.

How has Brexit affected Northern Ireland?

A majority of Northern Ireland’s people—almost 56 percent—voted for the UK to remain in the EU. The DUP was alone among Northern Ireland’s main parties in supporting Brexit. A significant amount of direct funding was at stake: since 1995, the EU has provided Northern Ireland with more than 1.5 billion euros for peacebuilding and reconciliation programs. Despite Brexit, the EU and the UK have agreed to extend the joint funding program through 2027.  

The most contentious issue has been Northern Ireland’s border with the Republic of Ireland. The border, which was heavily militarized during the conflict, has since become essentially invisible, with people and goods crossing freely. This was possible in large part because both Ireland and the UK were part of the EU’s single market, the common set of regulations that allows for the free movement of goods, services, people, and money within the bloc.

But with Northern Ireland and the rest of the UK having officially left the EU, this has changed. Throughout Brexit negotiations, EU, Irish, and UK officials all sought to avoid the return of a hard border, fearing that checkpoints could complicate trade, revive tensions between communities, and open the door to renewed violence. Yet London’s commitment to leaving the EU single market and customs union made some sort of border checks inevitable. The new relationship between the EU and the UK, negotiated over the course of 2020 and implemented starting in January 2021, settled on a complicated solution to this thorny problem: the Northern Ireland Protocol.

What is the debate over Brexit’s Northern Ireland Protocol?

Like the rest of the UK, Northern Ireland is no longer part of the EU customs union, the basis for common tariffs on all goods entering the bloc. That means customs checks are necessary. However, to avoid a hard border with the Republic of Ireland, those checks instead take place between Northern Ireland and Great Britain; this, in effect, creates a new border in the Irish Sea. Meanwhile, Northern Ireland—but not the rest of the UK—continues to follow many of the EU’s single-market regulations, allowing the land border with Ireland to remain open. Additionally, the protocol is aided by a separate Ireland-UK agreement that allows free movement of people between the two countries.

An infographic of the Northern Ireland Protocol, showing that goods going from Great Britain to Northern Ireland are checked at portsBut the protocol has spurred backlash from unionists. The DUP, which supported Brexit as a way of drawing closer to the UK, now sees the Irish Sea border checks as driving a wedge between them; many rank-and-file unionists likewise interpret London’s support for the protocol as a betrayal. This grievance helped spark riots in April 2021, the worst violence Belfast had seen in decades, and has caused the DUP’s ongoing boycott of the Northern Ireland executive.

To break the impasse and address unionist concerns, in early 2023 the EU and the UK government under Prime Minister Rishi Sunak struck a new deal known as the Windsor Framework. It created a “two-lane” system in which goods staying in Northern Ireland are exempted from checks while those destined for Ireland are still required to undergo inspection. It also gives Stormont the ability to veto some EU regulations, among other measures. Unionists nonetheless maintained their opposition for nearly a year, arguing the framework did not go far enough. But the DUP relented after the January 2024 update offered several additional compromises, including further reducing border checks, reaffirming Northern Ireland’s constitutional role in the UK, and earmarking nearly $4 billion in new funding for the revived Stormont government.

What is the future of the peace process?

Some observers have long feared that the UK’s departure from the EU threatens the Good Friday Agreement; they include Tony Blair, the UK prime minister who presided over the accord. The previous Irish prime minister, Leo Varadkar, echoed this point in March 2018, arguing that Brexit “threatens to drive a wedge between Britain and Ireland, between Northern Ireland and the Republic of Ireland, and potentially between the two communities in Northern Ireland.” Sinn Fein leaders have called Brexit “the most serious threat in the history of the peace process.”

That is because the Good Friday Agreement established intricate arrangements among the various parties. The Three Strands of the pact created a web of institutions to govern Northern Ireland (Strand One), bring together leaders in Northern Ireland with those in Ireland (Strand Two, or North-South cooperation), and bring together leaders from throughout the UK and Ireland (Strand Three, or East-West cooperation). There are currently more than 140 areas of Northern Ireland–Republic of Ireland cross-border cooperation, including on health-care services, energy infrastructure, and policing. Many experts and political leaders fear that any disruption to this cooperation could undermine trust in the agreement and thus the basis of peace in Northern Ireland.

Though British and Irish leaders have pledged to protect the Good Friday Agreement, some Brexit supporters have seized the opportunity to criticize the deal’s power-sharing institutions, arguing that the pact is outdated. Some in the DUP, which opposed the agreement in 1998, have increasingly questioned the arrangements it established. Experts worry that the rancor over the Brexit deal’s trade provisions has fed a growing sense among Northern Ireland’s Protestants that the Good Friday Agreement itself is failing to represent their interests. 

Yet another pressing question is whether Brexit could lead Northern Ireland’s people to vote to leave the UK and join a united Ireland, a possibility the Good Friday Agreement allows for. Since the 2016 Brexit vote, Northern Ireland’s nationalist and republican leaders have pushed for such a referendum. It would require London’s approval, as well as a separate vote in the Republic of Ireland. Analysts say that Sinn Fein’s growing electoral influence in both Northern Ireland and the Republic of Ireland has made that more likely, and First Minister O’Neill has called this the “decade of opportunity” for unification. However, many experts also say that Sinn Fein’s recent success in Northern Ireland politics has largely been a result of the disarray among unionist parties rather than a rise in nationalism, and that public support for unification remains well below the necessary simple majority.

Mohammed Aly Sergie and Diana Roy contributed to this report.

Recommended Resources

The Congressional Research Service [PDF] examines the Northern Ireland peace process.

Ireland’s The Journal takes stock of falling unionist support for the Good Friday Agreement on its 25th anniversary.

This BBC explainer delves into the details of the Northern Ireland Protocol and the proposed Windsor Framework.

The University of Ulster operates an expansive archive of information and primary sources on the Troubles.

CFR President Richard N. Haass discusses the 2013 talks in Northern Ireland in a Foreign Affairs video.

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