Caroline Brett is Affiliated Lecturer in the Department of Anglo-Saxon, Norse and Celtic at the University of Cambridge. She was Research Associate on the Leverhulme-funded project 'Brittany and the Atlantic Archipelago' and has previously published an edition of two saints' lives from Brittany. Fiona Edmonds is Reader in History and Director of the Regional History at Lancaster University. She is the author of Gaelic Influence in the Northumbrian Kingdom: The Golden Age and the Viking Age, Studies in Celtic History (2019). Paul Russell is Professor of Celtic in the Department of Anglo-Saxon, Norse and Celtic at the University of Cambridge. His research interests include Medieval Latin in the Celtic-speaking world, learned texts in Celtic languages, Celtic philology and linguistics, and medieval Welsh law. He has recently published Reading Ovid in Medieval Wales (2017) and Vita Griffini filii Conani: The Medieval Latin Life of Gruffudd ap Cynan (2005) which won the 2004 Legonna Prize.