It is remarkable how little Scotland features in contemporary Northern Ireland politics and indeed vice-versa. In our book, Ties that Bind?: Scotland, Northern Ireland and the Union (Irish Academic Press), we show that both places have been, and remain, politically as well as culturally entwined, even if this has sometimes been obscured and seldom acknowledged. We demonstrate how central both places and their politics currently are to the question of the future of the UK Union.

The relationship between Ulster or the North of Ireland and Scotland is one of singular historical intimacy. Over the centuries numerous common bonds have been forged around themes as varied as religion (especially Presbyterianism), trade and industry, language, literature, music and sport. There have been substantial population movements between the two places, most notably from Scotland to Ulster in the 17th century, and the reverse flow during the 19th century.

Given such close ties of ‘kith and kin’, there was thus much anxiety in Scotland when the ‘troubles’ broke out in Northern Ireland at the end of the 1960s. Religious divisions in west-central Scotland and the ‘Orange and Green’ character of much popular culture seemed to hold the potential for discord to spill over. However, there was little inclination in Scotland to politicise the Northern Ireland problem; moreover, Scotland’s political development during the 20th century around the left-right politics of Britain as a whole was at variance with those in Northern Ireland where the community division over the constitutional question left little room for political appeals that were not of an ‘Orange or Green’ kind.

Scotland in effect kept the troubles at bay, but the price of this was the relative absence of Scottish contributions to efforts to find a solution. There was no Scottish ministerial presence in the Northern Ireland Office after the imposition of Direct Rule in 1972 until the much more promising political context of the 1990s. In 1985, following the signing of the significantly named ‘Anglo-Irish Agreement’, a Glasgow Labour MP admitted in the House of Commons that Scotland’s voice in the debate had not been heard, and that this was all the more regrettable given that Scotland was the part of Britain with most in common with Northern Ireland and best able to comprehend the complexities of the problem.

The changed political circumstances of this century require more awareness and frank acknowledgement of the political issues which bring Scotland and Northern Ireland together, and suggest the need for more positive interaction. For those in Scotland who recoil from such a prospect we would remind them that there are many Scotlands and there is certainly one that cares about Irish matters and relations between Scotland and Northern Ireland especially. Few would doubt that Scotland becoming independent would have far-reaching effects across the political landscape in Northern Ireland, while there is also the likelihood that moves towards, or the securing of, a united Ireland could have a de-stabilizing impact on certain communities in parts of Scotland. For decades Scotland and Northern Ireland were the drivers, in their respective ways, of debates over devolution and constitutional change in the UK more broadly. In that transformative moment when the UK was radically re-shaped at the end of the 20th century both places received devolution with primary legislative powers. Moreover, the critical interrogation of the meaning, or meanings, of British identity was brought about by the Northern Ireland situation or the Scottish Question as the latter took on greater political force with the success of the SNP.

In our book we take issue with those commentators and scholars who simply discount the Irish dimension, whether in historical or contemporary perspective, in deliberations over Britishness. We argue that it is essential, and we take the view that including Northern Ireland helps us appreciate the varieties, ambiguities, untidiness, and slipperiness of the whole concept of British identity.

We also argue that Scottish politics, over the past fifteen years or so, have been ‘Ulsterised’. What we mean by this is that there has been a narrowing of political life in Scotland to the point where every other issue is subordinate to the ‘national question’, and where the language of ‘Unionists’ and ‘Nationalists’ is now as common as in Northern Ireland. Outgoing First Minister Nicola Sturgeon’s wish to make the next UK general election in Scotland a ‘de facto’ referendum on the independence question is perhaps the ultimate expression of this ‘Ulsterising’ effect. Moreover, it needs to be noted how much the recent political and media attention to religious sectarianism in Scotland merely underscores the extent to which this phenomenon echoes divisions in Northern Ireland and highlights the Irish roots of these tensions in Scotland.

Divergent support for Brexit in the 2016 referendum has severely tested the Union. Brexit has strengthened some political arguments for Scottish independence while further complicating the practicalities of partitioning Great Britain, while the separate Brexit settlement applied to Northern Ireland, the Protocol, continues to paralyse politics at Stormont. Historically the corridor linking Britain and Ireland, Northern Ireland is now also the place where, messily, the EU and the UK meet. With Brexit lacking the support of a majority in Northern Ireland and the Protocol lacking the support of any elected unionist representative, the architecture of devolution and power-sharing has been unable to withhold this strain.

The DUP’s refusal to enter a Northern Ireland Executive under the current Protocol has encouraged a vocal minority within unionism to imagine a rose-tinted future without devolution. We argue that any nostalgia for a variation of Direct Rule is a dead-end for unionists. It ignores the shape and priorities of the new Northern Ireland electorate, and embraces rallying a smaller unionist base over the challenge of reversing recent electoral losses. The continuing absence of Stormont also sets Northern Ireland apart from the rest of the devolved UK. Legitimate criticisms of the devolved settlement made across the UK – most notably with regard to poor public policy outcomes, the incoherent role of central government, and the lack of common endeavours across the Union – lose credibility when they imagine a unitary UK state as a politically viable alternative.

Despite the favourable conditions provided for Scottish and Irish nationalism by the turmoil of British politics in recent years, the constitutional future of the UK is still very much up for grabs. Polls suggest that the surge in support for nationalism widely seen as inevitable in both places has, as yet, not occurred. Whether the Union breaks or is remade the ties between Scotland and Northern Ireland will remain a vital component of our shared history and an uncertain future across the narrow sea.