Some of my research has concentrated on periods of conversion to Christianity, including the English in the seventh century and Scandinavians in the ninth, tenth, and eleventh. Most recently I published ‘Bede, Gregory, and Strategies of Conversion in Anglo-Saxon England and the Spanish New World’ (Jarrow Lecture, 2015), an exercise in comparative history. I am also interested in all aspects of the Scandinavian world in the early middle ages, including viking military activity and the history of Scandinavia and the overseas settlements. Within this broad field, I have worked particularly on Scandinavians outside their homelands, applying an interdisciplinary and comparative approach to issues of integration and interaction between incomers and established societies, while also considering what far-flung Viking-Age populations had in common. My recent published work on these subjects includes 'Diaspora and Identity in the Viking Age', Early Medieval Europe 20:1 (2012), 17-38, 'Early Normandy', Anglo-Norman Studies 35 (2013), 45-64, and ‘Connections and Exchange in the Viking World’, Byzantium and the Viking World (ed. F. Androshchuk, J. Shepard, and M. White) (Stockholm, 2016), pp. 27-52. Although I have retired from formal teaching, I am continuing to research in these fields. My current project is a study of political baptisms and the conversion of viking armies in ninth- and tenth-century Francia.