Of the three major Reformers, Zwingli remains the least studied and the least understood. That, as Bruce Gordon points out in his excellent new biography, has a lot to do with the uncomfortable legacy left by Zwingli's manner of death: the preacher died in battle. Gordon does not shy away from this fact, as many others have, and instead embraces it. The book's title is not accidental. It is well-chosen and it signals a set of themes that will run throughout the author's highly engaging account of this oft neglected but profoundly formative leader of the Reformation.

The first two chapters, titled ‘Mountain Valley’ and ‘Humanist Priest’, set the tone. The basic contours of Zwingli's early life are fairly well-known to scholars – in part because there is so little to know; documentary evidence is scarce. Zwingli left few autobiographical insights or written works from his time before Zurich. Gordon makes the most of what there is. As he deftly illustrates, what we do know about Zwingli's early years is vitally important for understanding his later trajectory. Born in a wealthy peasant family in an alpine village, Zwingli's ‘formation…was dictated by a deep-rooted attachment to land and people, by the faith of his parents, by an acute sense of the depredations in God's world, and by ever-present violence’ (p. 11). Landscape motifs, drawing from those mountainous vistas, played a prominent role in Zwingli's language throughout his life. So, too, did his sympathy for the simple lives and values of his peasant neighbours. Although he would attain international acclaim and participate in a Europe-wide network of correspondence, he remained self-consciously Swiss. At least at first, he saw his main opponents not in the pope but in the traditional Swiss nemesis, the Habsburgs. His patriotism, as Gordon's subsequent chapters show, ran deep, seemed at times all-consuming, but was also multi-layered and complicated. Zwingli, more than Luther and arguably even Calvin, aimed his Reformation at both faith and society; the two remained inextricably linked. Gordon compellingly argues that only by understanding this link can one begin to make sense of the Reformer's taking up arms and riding into battle. The enemy was not just internal, but embodied by all those who opposed the preaching of the word and the creation of a unified Reformed Confederation.

Zwingli's early years contain another key to understanding his later career: his passion for learning and his humanist education. Inspired by Erasmus, Zwingli crafted an ethos of spiritual renewal that was based in humanist ideals of the Renaissance. As Gordon observes, Zwingli – perhaps alone among the Reformers – is prepared to count classical figures such as Hercules and Socrates among the blessed. The Zurich Prophezei, which after 1525 gathered scholars to study and ultimately translate into German the entire Bible, represented ‘Zwingli's ideal of Church and pastor – scholarship at prayer’ (p. 142). The Reformer's humanist prioritisation of the spiritual informed his doctrine of God and especially his iconoclasm: ‘God is Spirit, Zwingli preached, and should be worshipped in Spirit’ (p. 101). It also shaped his eucharistic theology, famously bringing Zwingli into bitter conflict with Luther, as Gordon details in chapter 7. On the other hand, such commitments could be unwittingly elitist and may help explain why Zwingli alienated so many of the same rural people for whom he expressed outward sympathy. In Gordon's assessment, Zurich's ‘Reformation was a movement not of the people, but of educated men working within the system’ (p. 136).

By focusing significant attention on Zwingli's time as a priest and pastor, Gordon reminds us that this, too, distinguishes him from the other major Reformers. Unlike both Luther and Calvin, Zwingli spent decades in the parish, and his reforms emerged organically from those foundational experiences both prior to and within Zurich. Among those was a lifelong antipathy towards the Swiss mercenary trade, forged first-hand during his time with congregations and as a field chaplain on campaigns. Gordon provides a nuanced account of those views and their implications, both theological and political, exploring, too, the contradictory image of a preacher opposed to soldiering but deeply steeped in military culture, fond of martial metaphors and ultimately urging war and taking up arms himself.

Gordon's decades of research and writing on the Swiss Reformation allow him to craft an especially rich account of the complex political activities which were central to Zwingli's reforming work. Both his various allegiances and conflicts within Zurich's Large and Small Councils, as well as his manifold interactions with church and secular leaders outside the city are given extensive and insightful treatment. What emerges is another distinctive feature of this Reformer: he worked cooperatively. In Gordon's telling, Zwingli was no Einzelkämpfer, but a man who knew how to work with others and whose project was built upon those networks of cooperation featuring figures such as Wolfgang Capito, Martin Bucer, Johannes Oecolampadius and many more. As a result, the Reformation emanating from Zurich was far less tied to the person of its leading figure than those of Wittenberg and Geneva. That also allowed it to survive Zwingli's premature death and to be carried forward relatively seamlessly by his successor Heinrich Bullinger.

If Zwingli's legacy has attracted less attention than that of other Reformers, Gordon's biography makes a compelling case for why that should change. For one thing, the reader encounters a fascinating figure whose complexities and contradictions are handled fairly and engagingly. Not since George Potter's work, published nearly fifty years ago, has an English-language biography of Zwingli presented such a rich account of this Reformer. In addition, one of Gordon's particular strengths lies in his ability to trace Zwingli's legacy and connect his story to the present. It is certainly true – though frequently forgotten – that, as Gordon observes, Zwingli was ‘the originator of a new form of Christianity that became the Reformed tradition’ (p. 275). In order to understand more deeply the main features of that tradition, including its special blend of spiritual renewal and societal reform, its commitment to education and learning, its distinctive view of prophecy and the nature of the church and its single-minded focus on the word, one will need to look to Zwingli. And this biography is an ideal place to start. It is suitable both for general readers and for specialists.