After leaving school in 1964 he began studying political science, history and economics at the Westfälische Wilhelms-Universität Münster, Munich and at the Freie Universität Berlin, which he left in 1969 as a graduate in political science. He became a research assistant at the Institute of Political Sciences at the FU Berlin. In 1970 he became a research fellow at the Secret Prussian State Archives of the Prussian Cultural Heritage Foundation.