Essay International

Brexit and the Two Irelands

by Ophélie Siméon , 4 May 2020

Signed in 1998, the Good Friday Agreement brought the three-decade civil war in Northern Ireland to an end. Most significantly, the treaty opened the Irish border, a move that played a key part in the peace process. But as Brexit looms, the border might be shut back once again.

Signed in 1998, the Good Friday Agreement brought the three-decade civil war in Northern Ireland to an end. Most significantly, the treaty opened the Irish border, a move that played a key part in the peace process. But as Brexit looms, the border might be shut back once again.

On June 23, 2016, 51.9% of UK voters cast their ballot in favour of Brexit. Things are a tad more complex, however. The country is indeed made up of four nations (England, Scotland, Wales and Northern Ireland), each with its own culture and political traditions. Since 1998, these specificities have been enshrined in the devolution system, a governance framework that grants partial political autonomy to Wales, Scotland and Northern Ireland. In this context, the Brexit referendum has undoubtedly revived a host of deep-seated geopolitical and historical tensions. Unsurprinsingly, 62% of Scottish voters embraced the “Remain” side, as the nation largely supports the Scottish National Party, which demands independance within the EU. [1] The “Leave” vote prevailed in England and Wales, two regions which have turned increasingly Eurosceptic since the 1970s and 1980s. Conversely, 56% of Northern Irish voters chose to remain in Europe (fig. 1). [2] This last result may come as a surprise. Though the Republic of Ireland has a strong Catholic tradition, Northern Ireland has been dominated since the 17th century by a Protestant ruling class of Scottish and English descent. Having remained loyal to the British Crown, the region—known as Northern Ireland or Ulster—refused to unite with the southern Irish counties in 1921-22. Consequently, if the Republic of Ireland (Éire) reached full independence in 1949, but Ulster still remains part of the UK.

Fig. 1: The Brexit referendum results (June 2016).
Source: Mark Bailoni, « Géopolitique de l’austérité-Mutations de l’espace politique et renforcement des clivages au Royaume-Uni depuis la crise de 2008 », L’Espace politique, 34, 2018, OpenEdition

Given this fraught history, how come that Northern Ireland did not side with England’s Eurosceptic vote? The answer is that Brexit potentially threatens the peace process in Ireland. Signed on 10 April 1998, the Good Friday Agreement put an end to three decades of civil war, the so-called “Troubles” (1968-1998). Based on the disarming of the IRA and on the principle of power-sharing between the Catholic and Protestant communities, the Agreement also opened the border between the two Irelands. Over the years, the free circulation of people and goods has helped lessen indentity-based tensions, but these could be revived in the event of a no-deal Brexit, since the status of the Irish border is yet to be determined. Indeed, this border holds a highly strategic role, being the only point of contact between the UK and the EU. [3] Furthermore, the Good Friday Agreement remains fragile due to persisting sectarian rivalries, which Brexit may bring back to the fore. This paper aims to shed light on the history, hurdles and potential impact of a particularly thorny Irish question, one in which economics, geopolitics and conflicting national identities are closely woven together.

A pro-Brexit Loyalist mural, Tigers Bay, Belfast.
Photograph by Stuart Bothwick

The Good Friday Agreement: a delicate balance

Thanks to the Good Friday Agreement, Northern Ireland was able to turn over a new leaf and move on from one of the darkest times in its history. The origins of the Troubles run deep. In the wake of the 1921 Partition of Ireland, Ulster became the locus of mounting hostility between a Protestant majority (known as the Loyalists or Unionists) wishing to remain in the UK, and a Catholic minority (the Nationalists, or Republicans) demanding full independence and a union with the south. [4] Each side had its own paramilitary militias. The IRA (Irish Republican Army) and the INLA (Irish National Liberation Army) fought on the Nationalist side, while the Loyalists had their UDA (Ulster Defence Association) and UVF (Ulster Volunteer Force), in addition to a variety of smaller organisations.

Sectarian violence reached an all-time high in the years 1968-1998. Militias not only fought one another; Nationalist groups also opposed the British army, which had been deployed to maintain public order in Northern Ireland. The IRA also carried out multiple bombing attacks in the region and in England, including an assassination attempt against Margaret Thatcher during the 1984 annual Conservative party Conference in Brighton. Around 3,500 people, mostly civilians, lost their lives during the Troubles. [5] Two specific events particularly shocked public opinion, thus cementing the idea that the conflict was entirely pointless. The “Bloody Sunday” first comes to mind. On 30 January 1972, the British army opened fire during a peaceful demonstration organised by a cross-sectarian group of activists in Derry/Londonderry, killing 14 people. Twenty-four years later, the IRA committed a lorry-bomb attack in Manchester, a city with an important Irish community. More than 200 people were injured, and degradation costs amounted to 700 million pounds. That same year, ahead of the 1997 general election, Labour candidate Tony Blair promised to make Northern Ireland one of his top priorities.

Fig. 2: Irish and Northern Irish counties and provinces since 1921.
Source: Fabien Jeannier, « Le Brexit et la frontière irlandaise », Géoconfluences, 22 janvier 2019.

The peace process enshrined in the Good Friday Agreement must be repositioned in a wider context, that of the nationalist revival in the UK’s Celtic regions. After being appointed Prime Minister in May 1997, Tony Blair agreed to bring devolution to Scotland, Wales and Northern Ireland, a regime which they had been demanding for many decades. Under this system, many key powers remain within the British government in London (such as defence, foreign affairs and international trade), while others (education, tourism, and, most crucially, local governance) are transferred, or devolved, to various regional parliamentary institutions. These include the Northern Irish Assembly of Stormont House, in Belfast. Consequently, the peace process both prepared and cemented Northern Ireland’s accession to partial political autonomy. Negotiations between Ulster and the British government were held over eighteen months. Crucially, the EU and the Republic of Ireland both acted as international guarantors. The Agreement was eventually signed in April 1998, and ratified the following month through an all-Ireland referendum. The Agreement rests on four pillars: disarming the IRA and the other paramilitary groups; sending the British troops back home; opening the border; and the sharing of power between Catholic and Protestant representatives. These officials were to be elected by proportional vote, and to sit in Stormont House.

However, some of the treaty’s clauses—and especially those dealing with sovereignty—gave rise to a variety of conflicting interpretations. According to the Loyalist, Protestant parties, such as the moderate Ulster Unionist Party (UUP) or the ultra-conservative Democratic Unionist Party (DUP), the Agreement confirms Northern Ireland’s place within the UK, as devolution would act as a bulwark against independence claims. Conversely, Republican parties such as the Sinn Féin and the Socialist Democratic Party (SDP) argue that the Agreement holds the key to a new form of popular sovereignty, free from the shackles of British power. In their opinion, the union with Britain is now officially meaningless, and devolution is a first step towards Irish reunification. [6]

Far from easing sectarian tensions, these disagreements actually reinforced them by giving a platform to the more radical elements within each community—namely, the ultra-Protestant DUP and the Sinn Féin, formerly the IRA’s political front. Consequently, enforcement of some of the Agreement’s key clauses was significantly delayed. For instance, the IRA laid down its arms only in 2005, while the British troops were only withdrawn between 2006 and 2007. Moreover persisting sectarian tensions ultimately brought the principle of power-sharing to its knees. The Northern Irish Assembly was thus suspended in 2002. Until its reopening in 2007, its executive powers were transferred back to the British Cabinet in London. The Assembly was suspended again in January 2017, as the two main parties (Arlene Foster’s DUP and the late Martin McGuinness’s Sinn Féin) had failed to form a coalition agreement. Since then, Northern Ireland has therefore been governed directly from London, just as Downing Street is struggling to implement its Brexit deal—a policy that Northern Ireland stands firmly against.

Despite these structural failings, the Good Friday Agreement has nevertheless led to substantial progress in one key area, since it has put an end to the civil war in Northern Ireland. According to political observers and public opinion alike, the open border between Ulster and Éire has played a key part in the peace process due to a threefold positive impact. First, from an economic point of view, the open border has reinforced trade relations between the two Irelands, to the point that the Republic is now Ulster’s first economic partner. Second, the disappearance of border controls has ended not only to a climate of generalised suspicion, but also Northern Ireland’s cultural isolation. Third, calls to violent action are on the wane, as both Catholics and Protestants are now largely keen on keeping the peace and moving on from the Troubles. [7] Yet Brexit might very well shatter this fragile balance.

Anti-Brexit Nationalist placard, Anderstown, Belfast.
Photograph by Stuart Bothwick.

The Irish border: a thorny issue

On 29 March 2017, the UK invoked article 50 of the Treaty on European Union. Since then, the Irish border question has been at the heart of the negotiation process. Yet a solution remains to be found. The necessity to keep the Irish border open, in accordance to the Good Friday Agreement, might be incompatible with the respect of post-Brexit sovereignties. The free circulation of people is not really an issue here, since neither Belfast nor Dublin are part of the Schengen area. But difficulties abound as regards the circulation of goods, since a border without controls would open the door to all kinds of illegal trade—not only drugs, but also consumer goods that are banned in the EU, such as US-farmed hormone-treated beef and chlorinated chicken.

It is in this very context that a provisional agreement was signed in November 2017 between the EU and Theresa May’s Cabinet. In keeping with its Northern Ireland Protocol, the treaty planned to implement a customs backstop which would have temporarily kept Northern Ireland in the single market, so that London and the EU would have ample time to reach a definitive agreement. Once Brexit was fully achieved, the UK as a whole (and therefore Northern Ireland) would still remain part of the European customs union, just like Monaco, Andorra, Turkey, the Channel Islands and the Isle of Man. [8]

The backstop was favourably received by Northern Ireland’s nationalist circles and by the Irish Cabinet of Leo Varadkar. [9] In particular, the promise to keep an open border between the two Irelands was perceived as a realistic solution in view of the state of Ulster’s economy. The border zone does play a key part in the nation’s trade exchanges, especially in the agricultural sector, which is dominated by small-scale cattle and milk farms. Usually located in the border counties of Derry, Strabane and Fermanagh, these holdings have developed strong economic links with the Republic, all the more easily that they share a Catholic tradition. In the case of the dairy sector, milk produced in Éire is often pasteurised and packaged in Ulster, before crossing the border once more to be sold in Irish and/or Continental supermarkets. [10] Therefore, a no-deal Brexit would no doubt have an extremely detrimental impact on the Northern Irish farming sector, insofar as it concerns the majority of exports to the Republic of Ireland.

Conversely, supporters the DUP and other supporters of a hard Brexit strongly disagreed with the backstop project. If the UK were to remain part of the European customs union, it would have to secure the EU’s prior approval to negotiate trade agreements with third countries, except for investment policies and the service industry. [11] And yet, Brexiters are hoping on a strong partnership with trade giants outside the EU, the United States most notably. Therefore, they view the backstop as a form of interference on the part of the EU, in keeping with textbook Eurosceptic rhetoric and its insistence on “taking back control” from Brussels.

Between 2017 and 2019, the British Parliament rejected the Cabinet’s Brexit proposals three times, thus also signalling its opposition to the backstop project. In the wake of Theresa May’s resignation on 24 July 2019, Boris Johnson’s overtly pro-Brexit government thus endeavoured to scrap its predecessor’s Brexit plan. The future of the Good Friday Agreement was therefore at stake once more.

The revised Northern Irish Protocol is not entirely new. Indeed, it partly reiterates a solution that London had originally rejected back in March 2017, at the beginning of the negociations with Brussels. In order to avoid a closed border and thus keep in line with the Good Friday Agreement, the Johnson government eventually agreed to keep Northern Ireland in the European customs union. This means that the border between the two Irelands will be moved de facto at sea and will now separate Ulster from the rest of the UK with the help of new border controls. [12] This option, which has provoked the Brexiters’ ire, might very well isolate Northern Ireland from an economic and geopolitical point of view, hence various proposals to avoid this. First, only goods destined to the local, Northern Irish market would fall into the jurisdiction of this customs union. However, they would have to conform to EU norms, and would be submitted to the EU’s customs duties. Second, to avoid re-establishing border controls between the two Irelands, the UK wishes to implement an online “smart border” for customs declarations. Third, the Protocol has introduced a key concept, that of “consent”. According to it, the final withdrawal agreement will have to be approved by the Northern Irish executive. Once the UK is eventually out of the EU, Northern Ireland will benefit from a transition period of at least four years, during which the nation will automatically remain part of the European customs union. Once the deadline has elapsed, Stormont House will have to give its consent for the agreement to be kept as is, and will then vote on the issue every four years. To sum up, according to the new Protocol, Northern Ireland will be part of the UK de jure, while remaining de facto a member of the European customs union. [13] But can this agreement be successfully implemented? Nothing is less certain.

Since the general election of December 2019, the Conservative party holds an absolute majority in the Westminster Parliament. The Johnson government now has a mandate to implement its pro-Brexit programme, and that includes the new Northern Irish Protocol. However, in Northern Ireland itself, structural difficulties are rife, and public opinion is widely divided on the issue. Furthermore, Stormont House has barely been in session since 2017. Even if the Northern Irish executive managed to get out of this political impasse, none of its parties have a clear majority within the devolved Assembly. Moreover, the DUP—the Conservatives’ historic political ally—sees the new Protocol as a betrayal, since it purports to keep Ulster partly under the EU’s aegis, in disregard of the principle of a “hard” Brexit. On top of that, this very Protocol does not mention any alternative in the event that Belfast rejects it after the four-year deadline. It thus makes it quite difficult to apply the very “consent” principle at the heart of this project. These uncertainties regarding the future of Northern Ireland have also revived deep sectarian tensions. Despite a widely shared will to keep the nation at peace, religious rifts and the various identities that underpin them are now back to the fore.

Brexit: the view from Northern Ireland and the return of sectarian tensions

In the wake of the 2016 referendum, the people of Northern Ireland felt that they had woken up “in a different country”. [14] Beyond sectarian and community rifts, the population largely agreed that a post-Brexit Ulster would be far removed from the ideals enshrined in the Good Friday Agreement of 1998. According to a 2016 joint survey from Queen’s University Belfast and Ulster University, 53% of respondents felt that Brexit would have a negative impact on Northern Ireland from an economic and geopolitical viewpoint, while 48% feared that it would hinder the peace process. [15] This feeling of general uncertainty and pessimism has not simply revived old sectarian tensions. It has also reawakened the traumatic memory of the Troubles.

Since the peace process is indissociable from the free circulation of people and goods between the two Irelands, the possibility that the border might be closed again has awakened fears that violence, too, might return. [16] These fears are not entirely unwarranted. Despite the ceasefire agreement signed in 1998, many paramilitary groups are still active. According to the 2015 Assessment on Paramilitary Groups in Northern Ireland, these organisations still survive to this day under the guise of sleeper cells. The issue of their disarmament therefore remains open. According to various police reports, there is a striking correlation between some of these groups and the world of organised crime, notably regarding weapons- and drug trafficking. The Northern Irish public is also wary of a new phenomenon: since the Good Friday Agreement, some paramilitary groups have also emerged in direct opposition to the peace process. This is notably the case for the New IRA (or NIRA), which has been acting as a magnet for various dissident Nationalist organisations since 2012. With around a thousand members, the NIRA sees the Good Friday Agreement—and the power-sharing principle lying at its core—as a betrayal to the Nationalist cause. Unsurprisingly, it intends to make the most of the rampant, Brexit-induced feeling of anxiety in Northern Ireland to take back the arms and put an end to the partition of Ireland. And indeed, dissident Republicans have engaged in widespread violent action since the 2016 referendum. In early January 2019, the NIRA carried out a bombing attack on the Derry/Londonderry courthouse. On 18 April of that same year, journalist Lyra McKee was shot dead by a stray bullet while covering a violent fight between the Derry police and NIRA members who had been suspected of concealing ammunition. Northern Irish politicians unanimously condemned McKee’s murder, and her passing created an outcry among the population, who saw it as a harsh reminder that peace was still a long way ahead. [17]

Despite wide-ranging peacekeeping attempts in Northern Ireland, Brexit therefore acts as a reminder that the sectarian tensions of old are not entirely in the past. It also shows that Northern Irish society is still profoundly divided over identity and religious issues in spite of the Good Friday Agreement. An ideal of inclusivity lies at the core of the treaty, in a bid to grant both Catholics and Protestants an equal role in building a new society. In addition to the reopening of Stormont House, the same principle also explains why many Trouble-era paramilitaries were pardoned and released from prison. But the inclusivity principle has also hindered the establishment of a transitional justice process in the name of national reconciliation. There has been no Truth and Reconcilitation Commission similar to thoseset up in South Africa, Canada and other countries. [18] While trying to move on without officially confronting the memory of the Troubles, the Good Friday Agreement has thus “[created] a truce that contains the historical antagonism without transforming the communal divide”. [19]

Under these circumstances, peace does not amount to harmonious cohabitation, and the rapprochement between Northern Ireland’s Catholic and Protestant communities has been all but easy. The “Peace Bridge” in Derry / Londonderry is a case in point. Inaugurated on the River Foyle in 2011, it was built to bridge a geographical and psychological gap, as the city had been historically cut into two, with a Protestant East bank (the “Waterside”) and a Catholic West Bank (the “Bogside”). The bridge has become a byword for a city that has managed to reinvent itself as a tourist destination, thereby moving on from its painful past. However, the monument has also been repeatedly vandalised. In addition, several hate crimses have been committed there. The border somehow lives on in the minds.
More generally, the Good Friday Agreement has failed to redefine Northern Ireland’s national identities. These were historically constructed in opposition to the “other” community, which was perceived as antagonistic. [20] Even though these enmities now rarely result in violent direct action, they are still a reality, as shown by Derry and Belfast’s highly segregated neighbourhoods. Likewise, inter-religious marriages remain a minority. In other words, the Northern Irish still define themselves based on their religion, and these beliefs in turn largely condition national identities. Then, like now, Catholics see themselves as Irish, whereas Protestants identify as British. There is therefore no unified Northern Irish identity to speak of. [21]

The 2016 referendum results reflect these divisions. On the one hand, the “Remain” vote won due to a new generation of younger, less religious Protestants who find themselves at odds with traditional, ultra-conservative, DUP-led Unionism. On the other hand, Catholic Nationalists form the bulk of the anti-Brexit cohort in Northern Ireland. According to them, leaving the EU would further isolate the nation from a geographical, political and economic point of view, thus shattering any hopes of reunification. Conversely, Unionists have historically adopted a Eurosceptic stance, as they see the EU as an obstacle to the integrity of the United Kingdom. As a consequence, Protestant counties, and especially those dominated by the DUP, have accounted for 53% of the pro-Brexit vote in Northern Ireland. [22]

It is therefore highly difficult, under these circumstances, to apply the principles of consensus and conciliation at the heart of the Good Friday Agreement, especially since the upcoming Brexit has revived Irish nationalist claims. While the Northern Irish executive remains paralysed, and while the political situation in Great Britain is more uncertain than ever, the Republicans are hoping to seize a historic opportunity to realise the reunification of Ireland. In an interview with the Evening Standard from 24 October 2019, Sinn Féin vice-chair Michelle O’Neill reaffirmed the Nationalists’ key argument. Whether Boris Johnson’s Northern Irish Protocol is implemented or not, it contradicts Northern Ireland’s popular sovereignty as expressed during the 2016 referendum, since it seeks to impose Brexit on a nation that refuses it. This is why the Sinn Féin is asking for a new referendum on Ireland’s reunification in the next few years, while arguing that “the future of a new and agreed Ireland has to be one where Irish identity and British identity live side-by-side”. [23]


The Northern Irish question, and in particular the status of the Irish border, is one of the most complex aspects of the Brexit negociation process. Aside from the often fractious relationship between London and Brussels, the Good Friday Agreement’s political legacy looms large over the two Irelands’ shared history and future. Beyond persisting sectarian divides, the general fear that violence might return is evidence that the traumatising memory of the Troubles is still etched in the minds, despite the relative success of the peace process. The border is still at the core of Northern Irish identities, and remains a focal point in inter-community tensions.

Northern Ireland’s place in Europe also questions its very status within the United Kingdom, even as the smart border project seems to favour the Nationalists over the Unionists. At this point, and at a time when Brexit negotiations have been put on hold due to the Covid-19 pandemic, it is still too soon to draw conclusions on the future of the UK, let alone the possibility of a reunited Ireland. One thing is certain, however: aside from political slogans and public calls to “take back control”, Brexit sheds light on a wide range of deep-rooted tensions between Ireland and Britain, fraught with geopolitical and identity issues. In so doing, the divorce between the United Kingdom and the European Union raises many more questions than it answers.

by Ophélie Siméon, 4 May 2020

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[1Scottish Government, “Scotland’s Place in Europe”, December 2016.

[2Doherty et al., “Northern Ireland and Brexit : the European Economic Area Option”, European Policy Centre, 7 April 2017.

[3John Doyle et Eileen Connolly, “Brexit and the Future of Northern Ireland”, in Federico Fabbrini (ed.), The Law and Politics of Brexit, Oxford, Oxford University Press, 2017.

[4While often used interchangeably, the terms “Loyalist” and “Unionist” are not entirely synonymous. “Loyalist” actually refers to a non-moderate Unionist. Similarly, Republicans (usually affiliated with Sinn Féin and the IRA) are hardline Northern Irish nationalists.

[5Conflict Archive on the Internet (CAIN), University of d’Ulster, accessed on 27 October 2019.

[6Jennifer Todd, “The Vulnerability of the Northern Ireland Settlement : British Irish Relations, Political Crisis and Brexit”, Études irlandaises, n°42, 2015, p. 61-73.

[7D. Morrow, G. Robinson et L. Dowds, “The Long View of Community Relations in Northern Ireland : 1989-2012”, ARK Research Report, 2013, quoted in Todd, op.cit.

[8Jean Quatremer, « UE-RU : un deal mais toujours des doutes », Libération, 17 October 2019.

[9“Varadkar : Removing backstop ‘is effectively no deal’”, BBC News, 15 June 2019.

[10Sean Clarke, Daniel Levitt and Pablo Gutiérrez, “A typical hour in the life of the Irish border”, The Guardian, 3 September 2019 ; “Cross-Border Supply Chain Report”, 21 June 2018, Northern Ireland Statistics and Research Agency (NISRA).

[11Quatremer, op.cit.

[12Mark Bailoni, « Du backstop à la smart border : quand le Brexit bouscule la notion de ‘frontière’ », Libération, 2 October 2019.

[13Lisa O’Carroll, “How is Boris Johnson’s Brexit deal different from Theresa May’s ?”, The Guardian, 17 October 2019.

[14Paula Devine, Cathy Gormley et Arthur Aughey, “Waking up in a different country : Brexit and Northern Ireland”, ARK Research Update Report, June 2017.

[15Northern Ireland Life and Times Survey, 2016, accessed on 15/11/2019.

[16Wesley Hutchinson, “La dimension irlandaise”, Outre-Terre, “Brexit”, 2016, vol. 4, n°49, p. 154-165.

[18In South Africa, the Truth and Reconciliation Commission examined the legacy of the apartheid. In Canada, a similar institution dealt with the forced assimilation of First Nation people within residential schools.

[19Timothy White, “Generational Change and Redefining Identities: Post-Conflict Peacebuilding in Northern Ireland”, The Canadian Journal of Peace and Conflict Studies, vol. 45, n°2, 2013, p. 95-117.

[20Orla T. Muldoon et al., « Religious and National Identity after the Belfast Good Friday Agreement, Political Psychology, vol. 28, n°1, 2007, p. 89-103.

[22Mark Bailoni, Géoconfluences, 2017.

[23Sophia Sleigh, “Sinn Féin: Leaving EU will lead to united Ireland in a generation”, The Evening Standard, 24 October 2019.

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