My research focuses on culture and religion c. 400-900. I am particularly interested in the movement of ideas and people across Eurasia and Africa and the consequences of the exchanges involved. My principal areas of expertise are:

• the development of scientific and medical cultures
• ideas about the apocalypse as drivers of social change
• saints and hagiography

Increasingly what links these for me is how societies deal with crisis and rupture in political, religious, and environmental spheres.

My work has been funded by the AHRC, the Leverhulme Trust, and the British Academy.

I am the author and editor of several books. My latest, Charlemagne’s Dream: The Rise and Fall of the Carolingian Empire is out in Oct 2026. After that, I am writing a history of the Goths and the Fall of Rome.

Early medieval religion, culture, sciences, global histories.

I was born in Nottingham and studied in Sheffield (BA and PhD) and Cambridge (MPhil). I held posts at the universities of Leicester and Nottingham, before moving to St Andrews in 2007. I was a cross-faculty pro dean for research postgraduates 2014-18 and I have been a full professor since 2018.