In the preface to From partition to Brexit: the Irish government and Northern Ireland, Donnacha Ó Beacháin reiterates the oft-made point that Northern Ireland is ‘arguably the most researched piece of territory per capita in the world’ (p. xii). Yet, Ó Beacháin has identified a gap in this vast literature, specifically the tendency in most accounts to make only cursory reference to the Irish government's role in the conflict. This is a surprising but generally accurate observation. Cross-border violence was a daily occurrence from the early 1970s. The I.R.A. regularly used the frontier as a staging post, while loyalist attacks on the south, particularly in the 1970s, were frequent. Additionally, there were more than 120 conflict-related fatalities south of the border. Meanwhile, the Irish government was centrally involved in a range of peace initiatives from the Sunningdale Agreement in 1973 through to the Anglo–Irish Agreement in 1985 and most recently the 1998 Good Friday Agreement, as well as its offspring the St Andrews Agreement and the Stormont House Agreement. Despite the obvious impact that the conflict had socially, politically and economically, relatively little has been written on the Irish government's relationship with Northern Ireland. The public debate about a hard or soft border in the context of Brexit has once again emphasised the cross-border nature of the conflict and made this an opportune time to revisit the topic.

Ambitiously, Ó Beacháin covers the period from 1920 right up until 2018. It is a highly accessible read and, as the title suggests, geared towards a broad audience. Nonetheless, the range of sources used is impressive including archive material from the revolutionary period, party political archives and state papers. Complementing these sources is a series of elite-level interviews with a diverse range of political figures. Ó Beacháin was aided in the research in that his previous publication – Destiny of the soldiers: Fianna Fáil, Irish republicanism and the I.R.A. 1926–1973 (Dublin, 2010) – covered some of the same ground.

The first three chapters deal with the period up to 1969 in chronological order. The discussion of the beginnings of partition is particularly interesting. The aggressive post-truce Northern Ireland policy associated with Michael Collins is examined in some detail. Similarly, the discussion of Anglo–Irish relations during the Second World War in the subsequent chapter is interesting. The three later chapters dealing with the recent Northern Ireland Troubles are perhaps the strongest. The colourful political careers of Charles Haughey, Jack Lynch and Garrett FitzGerald punctuate much of the discussion. Ó Beacháin illustrates how political progress sometimes was stymied by electoral cycles. Nonetheless, it is concluded that these rival ‘Taoisigh converged on policy fundamentals and merely diverged on style’ (p. 278). This goes against the popular perception but is in line with the consensus opinion of most others who have researched the period. In a wonderful line, Ó Beacháin argues that ‘the real disharmony was between [Charles] Haughey the Taoiseach and Haughey the opposition leader’ (p. 278).

It is claimed that between 1972 and the Downing Street Declaration in 1993 there was a remarkable consistency in Irish policy, regardless of which party was in office, with consistent opposition to the I.R.A. campaign being an ever-present feature (p. 277). This is a particularly important conclusion. The strongest academic critique of the Irish government's role during the Troubles is Henry Patterson's Ireland's violent frontier: the border and Anglo–Irish relations during the Troubles. Patterson's view is that successive Irish governments proclaimed their abhorrence of I.R.A violence but generally refused to take the issue of Provisional I.R.A. exploitation of their territory seriously, facilitating that organisation's ability to carry on its war. Ó Beacháin's research seems to contradict this view but he does not directly engage with Patterson's work which is unfortunate. More generally, other academic research relevant to the topic is not utilised; I am thinking particularly of the absence of references to Robert Lynch's The northern I.R.A. and the early years of partition 1920–1922 (Dublin, 2006), Diarmaid Ferriter's Ambiguous republic: Ireland in the 1970s (London, 2012) and Eunan O'Halpin's Defending Ireland: the Irish state and its enemies since 1922 (Oxford, 1999).

Overall, this book does what it sets out to do: it is a ‘comprehensive and up-to-date overview of how political leaders in Dublin have struggled to adapt to partition’ (p. 272). While the current focus of attention in Anglo–Irish relations is on Brexit, a border poll in the not-too-distant future is a possibility. From partition to Brexit gives an excellent insight into how past experience of dealing with Northern Ireland has shaped the political landscape south of the border. This historic experience means that the prospect of unity may not be greeted with much enthusiasm in some political circles in the Irish capital.