I was educated at the University of St. Andrews and the University of Cambridge, where I completed a PhD under the supervision of R.W. Scribner. After finishing my doctorate I had a research stay at the Leibniz Institute of European History in Mainz before taking up a teaching position at the Queen's University of Belfast, where I lectured on early modern European history. During my time at Belfast I was the recipient of research awards from the British Academy and the Alexander von Humboldt Foundation and spent time as a Humboldt Senior Research Fellow in Wolfenbüttel, Berlin, and Vienna, where I was also a visiting lecturer in 2003. In 2012 I was elected an Affiliated Member for the Centre for Medieval and Early Modern Studies (Zentrum für Mittelalter- und Frühneuzeitstudien) at the University of Göttingen. At present I am a full-time researcher and writer and divide my time between Berlin, Vienna, and Venice.

The main focus of my research before my retirement from Queen's was on early modern religious history, primarily on the cultural and social aspects. I began as a specialist on the German Reformation and gradually broadened my approach, which ultimately led to my final book on the subject, which is a global history of early modern Christianity. Since completing this book I have moved on to new themes, which I discuss on the projects section.