This book attempts to place Germany's united Churches (combining Lutheran and Reformed) in historical and theological context and to consider them alongside recent efforts to integrate Protestant denominations in various parts of the world. Specialists in nineteenth-century German church history and theology will be drawn to parts A and B, written by Johannes Ehmann. Those interested in global trends in the twentieth and twenty-first century will find a diverse array of brief case studies by ten additional contributors in part D. The eight pages of part C are meant to serve as a bridge, though it is not clear why the short segment on the German Evangelical Synod of North America is located here rather than with the other international case studies in part D.

In part A (History), Ehmann traces the origins of united Churches in Prussia and the south-western and Middle German states. In all cases, the union of Lutheran and Reformed Churches coincided with state-building efforts in the aftermath of the Napoleonic wars and the transition from Holy Roman Empire to German Confederation. The Enlightenment had already weakened attachment to the historic confessions of faith that divided German Protestants, and the 300-year anniversary of the Reformation in 1817 fostered a climate of Protestant solidarity that aligned with state policy.

Part B (Theology) is a series of short sketches on Vermittlungstheologen (mediating theologians) who promoted and gave theological legitimacy to the united Churches. Friedrich Schleiermacher and Daniel Schenkel represented the liberal wing of this movement, Schleiermacher via a ‘radical historicization and contextualization of the Reformation confessions’ (p. 82) and Schenkel through his framing of the confessions as a foundation for German Protestantism as an ethical (and national) community. Other Vermittlungstheologen like Carl Immanuel Nitzsch, Carl Ullmann, Karl Friedrich Gaupp, Julius Müller and Johann Heinrich August Ebrard tried to steer a middle course between what they saw as weak religiosity on one side and rigid confessionalism on the other. Beyond differences in theology, liturgy and ecclesiology they imagined a higher Protestant unity that encompassed both Lutheran and Reformed traditions. Conservative proponents of the united Churches were content to substitute biblicism for confessionalism, but Old Lutherans rejected state-mandated reforms that undermined the distinct confessional identity of their congregations.

It is a bit jarring to transition from such an extensive and narrowly focused analysis of German church history to a series of brief essays on twentieth- and twenty-first-century efforts to unite Protestant denominations in West Africa, South Asia, North America and Europe. David N. A. Kpobi and Bernhard Dinkelaker describe a failed attempt to integrate diverse Protestant Churches in Ghana but note that interdenominational and interfaith cooperation and respect have improved none the less. Examples of successful unions appear in chapters by Barbara Rudolph (United Church of Christ in the United States), Yan Suarsana (Church of South India), Joël Dautheville (United Protestant Church of France), Jean-Francoise Collange (Union of Protestant Churches of Alsace and Lorraine), Susanne Labsch (Union of Waldensian and Methodist Churches in Italy), Charlotte Methuen (Scottish Union) and Martin Friedrich (Equmeniakyrkan in Sweden). The Church of South India stands out for its close relationship to Indian nationalism and independence from British rule in 1947. In other cases, motives included evangelisation, reconciliation social justice work and a commitment to ‘unity and diversity’ (p. 259). In some regions where Protestant Christians are a small minority, union also serves as a survival strategy.

A final essay by Anne Heitmann sums up what united or uniting Churches have to offer the broader ecumenical movement: ‘the ability to live with differences’, readiness ‘to give up one's own in favor of unity’, ‘rich experience … making room for others’ and service as ‘ambassadors for reconciliation and peace’ (pp. 259–60). One cannot help but notice the contrast between those contemporary ideals and the controversies over communion and ecclesiology that made integration so challenging in the early nineteenth century. The anti-Catholic inflection of nineteenth-century Protestant solidarity also stands in contrast to the ecumenical and interfaith work celebrated by various authors in part D. Regrettably, neither Ehmann nor the other contributors systematically explores such continuities and discontinuities, nor are other agendas transparent. Are the contemporary case studies (part D) supposed to shed new light on nineteenth-century German church history (parts A and B), or were the early German experiments a precursor to more recent efforts at integration? Do Germany's united Churches and Vermittlungtheologie offer lessons that might inform contemporary interdenominational and interfaith work? Ehmann does not say, at least not directly. Nevertheless, the book at least situates what we might be tempted to see as a national (or proto-national) story in a transnational context that invites comparative analysis. That accomplishment is significant in and of itself.