Born in 1947 in Borsum (Hildesheim district).
Studied from 1968-1972 in Göttingen (subjects: Latin / History / Auxiliary Sciences of History).
1973-1975 Research stay at the Deutsches Historisches Institut Rom (German History Institute in Rome).
Doctoral degree in 1976 in Göttingen.
Assistant at the Institute of History in Kiel (1977-1982) and Göttingen (1982-1986). Habilitation (post-doctoral lecture qualification) in Göttingen in 1989.
1988-1992 Research associate at the Deutsches Historisches Museum (German Historical Museum) in Berlin (including a major exhibition about Bismarck and designing smaller exhibitions).

1992-1995 Deputy Professor in Göttingen
1995/96 Deputy Professor at Freie Universität Berlin.

For the summer semester 1997 - appointment as the Chair for Medieval History and Auxiliary Historical Sciences at Kiel University
Retired on 1 October 2012.