Helen has been the editor of the Transactions of the Honourable Society of Cymmrodorion since 2008. She trained as a medievalist at the University of Sydney and the University of Oxford, specialising in Celtic Studies. Following completion of her PhD on the love poetry of Dafydd ap Gwilym, she spent three years as a postdoctoral fellow at the University of Wales in Aberystwyth. After teaching at the University of Sydney, Helen was appointed to a professorship at Swansea University, then to the Chair of Medieval Literature at the University of York, before taking up her present post in 2015 as Chair of Medieval Literature at the University of Bristol.

Helen has published many articles and edited collections on medieval literature, with a particular focus on medieval Welsh literature. She is the co-editor of The Cambridge History of Welsh Literature, published by Cambridge University Press in 2019. Helen has held management positions as head of department, head of school, and director of research. She is a Fellow of the Society of Antiquaries and she is currently the Vice President for Humanities, Arts, and Social Sciences at the Learned Society of Wales.