Donald Akenson's The Church of Ireland, published in 1971, was a bold historiographical experiment: declining, like Queen Elizabeth, to make windows into men's souls, the author instead set out to write what was in effect a business history, offering a strictly empirical assessment of the effectiveness of the Church, considered as an organisation designed to deliver certain services to a specific population. Nearly half a century later, Discovering the end of time plunges with equal boldness into the dimensions which that approach excluded. Focussing on the early career of John Nelson Darby, it seeks to reconstruct both the individual psychological conflicts, and the wider social milieu, out of which emerged the Dispensationalist theology that today has large numbers of Protestants, particularly in the United States, contemplating a vividly imagined future dominated by the Rapture, the Tribulation and the great battle of Armageddon.

Dispensationalism was a by-product of a broader growth of Evangelicalism within Irish Protestantism. Earlier accounts, by David Hempton and others, have located the heartland of this new spirit of religious fervour in the borderlands of south Ulster, and have sought its origins in the trauma endured by a vulnerable Protestant population during the insurrection of 1798. Akenson focuses instead on the counties of Wicklow and south Dublin. Wicklow too had its share of violence in 1798. But Akenson's concern is rather with the development there, in convenient proximity to the capital, of a close-knit society of affluent, largely resident, and religiously committed gentry and aristocrats. In this hot-house world a network of zealous clergy nourished dreams of reshaping their society through a mass conversion of the Catholic population, in the same way that their aristocratic patrons had converted mountain and bog into the designer wildernesses of their magnificent demesnes. To all of these Evangelicals the rise of O'Connell, and the national apostasy of Catholic Emancipation, brought bitter disillusion. For a minority, it encouraged a rejection of the very idea of an organised national Church. Against this background Darby, a troubled individual who had earlier sought to act out an ideal of early Christian asceticism in a remote part of the Wicklow mountains, developed a radical new theology for what became the Plymouth Brethren. In the grand scheme of successive divinely ordained dispensations, each arising out of the destruction of what came before, the cruelly disappointing circumstances of post-emancipation Ireland were merely evidence that all was going according to plan.

Discovering the end of time is a self-conscious work, studded with lengthy methodological meditations. At one point Akenson compares his argument to a braided line, where multiple strands confer strength and – crucially – the severing of any one strand does not rupture the line (p. 224). Such caution is understandable. Darby remained throughout his later life evasive about his early career, and some of what he did say was, as Akenson painstakingly establishes, untrue. The complex steps by which Darby developed his distinctive combination of ecclesiology and eschatology, equally, can be reconstructed only in part, from fragmentary accounts of a succession of theological conferences held during 1831–6. Here Akenson, already the author of books on the Hebrew and Christian Scriptures, and on the writings of St Paul, links close historical reconstruction to a confident overview of the key biblical texts on which the apocalyptic tradition has relied across the centuries, along with a penetrating analysis of the methods that Darby brought to their interpretation. All in all this new study is both a remarkable contrast to The Church of Ireland and a fitting companion piece.

Religion and greater Ireland stands at the confluence of several historiographical trends. The term ‘greater Ireland’ reflects a growing awareness that the Irish diaspora must be discussed in terms, not just of a patchwork of dispersed overseas communities, but of the connections between them. The resulting emphasis on networks brings recent work on Irish migration into line with British imperial history, where the same concept has recently become influential. And in the case of Ireland it is religion that provides one of the clearest examples of networks in action, as historians have begun to probe the mechanisms by which, throughout the English-speaking world, clergymen of Irish origin came to dominate the upper levels of the Catholic Church. The theme of an Irish Catholic spiritual empire is picked up in several essays, notably in Mark McGowan's analysis of how Irish bishops ruthlessly marginalised their French rivals across British North America. The global reach of Irish Protestantism also gets its due. Myrtle Hill offers a suggestive essay on the work in India and China of the Belfast-based Female Association for Promoting Christianity, while Michael Gladwyn shows how the substantial presence of Irish-born clergy (almost one in four before 1850) gave a distinctive character – confident, pugnacious and strongly anti-Catholic – to early Australian Anglicanism.

What gave the global dispersion of Irish Christianity its special character, as the editors emphasise, was the level playing field created by the absence of religious establishments. In response Irish Catholic clergy throughout the British empire displayed a loyalism that contrasted with the political ambivalence of their Irish-based colleagues. There were episodes of conflict. A well-rounded micro-study of chain migration by Dianne Hall demonstrates the prominence of Orangeism in the cultural baggage carried by migrants from south Ulster to the Kiama district of New South Wales. In 1920, as Jeff Kildea shows, a specific combination of events – the conscription crisis, insurrection in Ireland, a revived Catholic campaign for denominational education – produced an alarming but short-lived outburst of sectarianism in Australian politics. For the most part, however, the transfer overseas of Ireland's religious conflicts plays a surprisingly minor part in this volume. Instead essays as geographically diverse as those of Mimi Cowan on Chicago and John Stenhouse on Dunedin show Irish-born clergy and laity responding to their new environment by creating strategic alliances across ethnic and denominational lines.