Ruedi Hagen Keller is a German historian specializing in the history of the early and high Middle Ages. He works mainly on the Ottonian period, the Italian communes, and the culture of writing in the Middle Ages. Keller taught as Professor of Medieval History at the University of Münster from 1982 until his retirement in 2002. His collaboration with his colleague Gerd Althoff was particularly fruitful. With their work, Keller and Althoff made a decisive contribution to Münster's reputation in international medieval studies. Keller's research has had a considerable influence on German and international medieval studies since the 1980s and has led to a reassessment of early and high medieval kingship.
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Fruehmittelalterliche Studien Jahrbuch des Instituts fuer Fruehmittelalterforschung der Universitaet Muenster
2002
ISBN 9783110136937
Frühmittelalterliche Studien. Band 32
1998
ISBN 9783112421994
Frühmittelalterliche Studien. Band 33
1999
ISBN 9783112422014
Frühmittelalterliche Studien. Band 34
2001
ISBN 9783112422052
Pragmatische Dimensionen mittelalterlicher Schriftkultur
2002
ISBN 9783770537785
2007
2008
ISBN 9783110192391