How Irish Unity Got a Boost From Brexit and Demographics


In May 1921, the island of Ireland was split in two — giving rise to Northern Ireland as part of the United Kingdom, and to what would become the independent Republic of Ireland. A century later, the idea that reunification could happen one day has taken on new life. There’s little prospect of the referendum that would bring it about being held in the next five years, but shifting demographics, coupled with the forces unleashed by Brexit, suggest a ballot beyond then is possible — assuming the British government chooses to hold one.

1. Why was Ireland divided?

The 1921 partition was cemented by a peace agreement between British authorities and Irish rebels seeking independence after centuries of British rule. Northern Ireland, with a majority Protestant population (most descendants of settlers from Britain), remained part of the U.K. The largely Catholic southern part of the island became the Irish Free State, before formally declaring a republic in 1949.

2. Why talk of reunification now?

Brexit is one big reason. In a 2016 referendum, 52% of people in the U.K. voted to leave the European Union, but 56% of Northern Irish voters supported remaining. As in Scotland, where a majority also backed EU membership, being forced out of the 27-nation bloc stirred nationalist sentiment. Scotland’s government is pushing for another referendum on leaving the U.K., a grouping of four distinct nations that also includes England and Wales. Some 88% of Northern Irish who see themselves as “nationalists” — and support a united Ireland — voted against Brexit, compared with just a third who want Northern Ireland to stay in the U.K., known as “unionists.”

3. Why must the British approve a referendum?

It’s written in the Good Friday Agreement — the 1998 peace deal that largely ended three decades of bloody sectarian violence. Under the terms, only the U.K.’s Secretary of State for Northern Ireland can call a vote on Irish reunification — referred to as a “border poll” — and then only if it appears “likely” a majority there would back it. The accord doesn’t define “likely,” but scenarios include multiple surveys backing reunification or a consistent nationalist majority among Northern Irish lawmakers. If a referendum were defeated, another could only be held after seven years.

4. Does the Republic of Ireland also get a say?

Consent for reunification is required on both sides of the border under the terms of the Good Friday Agreement, meaning a referendum would take place in the republic, too. Polls in the south consistently back unity. An RTE-commissioned survey in March 2021 found 53% of respondents favored a united Ireland, 19% were against and 28% undecided. If Northern Ireland (population 1.9 million) voted against reunification, the measure would be rejected no matter what happened in the south (population 4.9 million).

How Irish Unity Got a Boost From Brexit and Demographics

5. Why do demographics matter?

Northern Ireland’s 2021 census may show Catholics outnumbering Protestants for the first time, with the results released in the fall of 2022. Not all Protestants are unionists and not all Catholics are nationalists, but religious identity tends to be a good indicator of attitude to a united Ireland. At the last census, in 2011, 48% identified as Protestant and 45% as Catholic. (In 1971, Catholics made up just 31% of the population.)

6. When will a referendum happen?

The Irish government said a poll should not be held for at least five years because of tensions fanned by Brexit. U.K. Prime Minister Boris Johnson said it wouldn’t happen for a “very, very long time.” A referendum anytime soon would be “dynamite,” according to former Irish Prime Minister Bertie Ahern, who helped negotiate the Good Friday Agreement. Outbreaks of sectarian violence in early 2021 underlined the point, with some unionists attributing the rioting to resentment about Northern Ireland’s different treatment than other parts of the U.K. under the Brexit agreement. To avoid reinstating a physical border between north and south — a move officials in Dublin, Brussels and London feared might inflame tensions — Northern Ireland remained in the EU’s customs area, meaning shipments from Britain must be checked to make sure they conform with EU standards.

7. What do surveys say?

Few if any polls in Northern Ireland have indicated a majority supporting reunification. A Sunday Times survey in January 2021 showed a slim lead for those wishing to remain in the U.K. — 47% to 42% — with 11% undecided. Still, the survey found that a majority want a referendum within five years. In a similar poll in 2019, there was just 38% support.

8. What are the obstacles?

All mainstream Irish political parties publicly aspire to eventually reunite Ireland. Yet other than Sinn Fein (the main nationalist party) most are wary partly because there would be a cost. As things are, the U.K. provides an annual subsidy of about 10 billion pounds ($13.8 billion) to Northern Ireland, a relatively poor region with high social spending that’s still rebuilding its economy after decades of violence. There’s also the potential difficulty of absorbing a unionist community opposed to the concept, some bitterly so. That said, a referendum in Scotland or the census results might shift opinion, as could the likely inclusion in Ireland’s government of Sinn Fein — winner of the popular vote at the last election and a force in the north whose core political objective is a united Ireland.

How Irish Unity Got a Boost From Brexit and Demographics

The Reference Shelf

©2021 Bloomberg L.P.

BQ Install

Bloomberg Quint

Add BloombergQuint App to Home screen.