was born in 1938. He studied history, classical philology and political sciences. 1967-70 he was a member of the Ostkolleg in Cologne, 1970-76 Assistant Professor at the Ruhr-University Bochum and 1976-92 Professor of Contemporary History at the University Bielefeld. Since 1993 Professor of Contemporary History at the University of Potsdam. He has published widely on social and political history of the 19th and 20th century.