This book, written by an eminent Irish historian based in Scotland, is very much of its time. The survival of the union with Scotland is uncertain, though that with Ireland looks less troubled now than in many decades. The author aims to “explain the survival of these two constituent unions of the United Kingdom” (8). A generation and more ago, Irish historians showed little interest in the Anglo-Scottish union of 1707, and Scotland featured little in the work of Irish historians. Comparisons of the two unions have been rare, with Albert Venn Dicey's work perhaps the most notable, especially given his status as a strident unionist polemicist. Alvin Jackson's conclusion is similar to Dicey's: a “capacious and flexible union” allows distinct institutions and patriotic sentiments to flourish within the components of the state while allowing for the development of statewide loyalties. Until half a century ago, the experience of these two unions suggested this was a winning strategy, but this permissive dualism now looks less successful in Scotland.

Scholars have long grappled with the conundrum, expressed by Walker Connor, one of the great scholars of nationalism, that nationalism “appears to feed on adversity and denial. . . . It also appears to feed on concessions” (“The Politics of Ethnonationalism,” Journal of International Affairs 27 [1974]: 21). A historical comparison of these two unions offers the opportunity to confront this conundrum. Unionism is simply the term used here and elsewhere for state nationalism, and as with other nationalisms, it is a shallow, highly malleable ideology, capable of being constantly redefined and reinvented. Historians have debated the causes and nature of the origins of these unions, but whatever the origins, unionist nationalism had the opportunity to reinvent itself. What distinguishes the two unions is less to be found in their origins than in the reinvented trajectories of unionism in Scotland as compared with its Irish equivalent.

What emerges from this meticulously researched book is the importance of the original unions in setting the path of postunion politics. The path-dependent nature of the original unions was important, though path dependence is not path determinism. As the history of each union demonstrates, there were ample opportunities to change paths. But what has been at least equally important is that institutions and policies alone are less significant than the myths that grow up around these institutions. Ernest Renan, the nineteenth-century scholar of nationalism, famously observed that the essential element of a nation is that its citizens have many things in common but have also forgotten many things. The failure of unionism in Ireland was its inability or unwillingness to encourage people to forget. Indeed, unionism in Ireland in its crassest form seemed all too willing to encourage the selection of memories that were most detrimental to its own cause. Commentators who remark on the Scots' capacity to dwell on historic grievances against the English fail to place this into any serious comparative framework. Unionists were far more sensitive in ensuring that postunion Scotland was offered little to resurrect old memories and myths.

Jackson takes us through the evolution of the two unions, but the density of the detail often obscures the overall message. There is ample material here to build a number of theses. The conclusion draws out some well-trodden themes, but these do not so much emerge from the narrative as seem safe and uncontroversial. The emphasis throughout is on the role of elites, the implication being that history is shaped by key figures in key institutions rather than by wider societal and economic forces. The decline of empire is emphasized and welfare plays a part in this narrative, but overall those whose consent is central to understanding the success or otherwise of union are paid little attention. There are exceptions, including a splendid passage when the author takes us on a journey through Victorian and Edwardian Belfast, passing place names and public spaces that would have reminded inhabitants of unionism. This banal unionism was everywhere. If he is less sure-footed in discussing Scotland, then that is simply because any other expertise would pale in comparison to his encyclopedic knowledge of Irish unionist history.

There are other unions that make up the United Kingdom, and it might have helped to consider more than the two that are or have been most troubled. The author refers to Colin Kidd's description of unionism in Scotland as “banal” (Union and Unionisms: Political Thought in Scotland, 1500–2000 [2008], 1) in earlier times, but there are other banal unionisms within these isles that might be set against these more troubled unionisms. Indeed, it seems odd to see the United Kingdom referred to as “union state” (7, 25) in these pages while the author makes much of the distinctions in origins and trajectories of the two unions under scrutiny. What emerges is less a coherent union state than a state of disparate unions, and that is after considering only two of the unions that contributed to the United Kingdom. This is conceptually important because it points to different dynamics that need to be explored, not to mention potentially very different futures.

This is an important book not least because of the timing of its publication. Unionism and Britishness are under scrutiny now as rarely before. This may be a book of its time, but it is likely to secure its place as a work that will be read well after the current political debates are forgotten or have become potent memories or myths.