Immo Warntjes is a graduate of the University of Göttingen (Germany) in history and mathematics. From 2003 to 2006 he was a post-graduate fellow in the Foundations of Irish Culture, 600–850 AD-project in the Moore Institute of NUI Galway (Ireland), where he completed his PhD under the supervision of Prof. Dáibhí Ó Cróinín in 2007. Since 2007 he is lecturer in Medieval History at the University of Greifswald (Germany). Besides late-antique and early-medieval computistics, his main areas of research include the use of languages in early medieval Europe, Irish political history, succession to high offices, and social mobility.