Thomas Arentzen is a Postdoctoral Research Fellow in the Faculty of Theology at the Universitetet i Oslo and currently a Fellow in Byzantine Studies at Dumbarton Oaks Research Library and Collection in Washington, DC. He is also a Reader in Church History at Lunds Universitet. He has published widely in the fields of Marian Studies, Byzantine homiletics and hymnography as well as Eastern Christianity. His books include Ortodoxa och österländska kyrkor i Sverige (2015) and The Virgin in Song: Mary and the Poetry of Romanos the Melodist (2017).