In May 1945 he was captured by the Soviet Army and subsequently sent for debris removal to the Auschwitz concentration camp before being transported to Kazakhstan, where he was held as a prisoner of war for 15 months until being repatriated to Germany on medical grounds.
He claimed that his personal experiences during the war were formative for his later academic direction, especially his interests in "crisis" and "conflict" and his sceptical stance towards "ideological" notions of moral or rational universalism and historical progress.
[1] He also claimed that the experience of being part of a defeated nation or culture enabled a more self-reflective form of historical understanding, and that the most interesting perspectives on history are often written by the vanquished rather than the victors.
Between 1972 and 1997 Koselleck co-edited, together with Werner Conze and Otto Brunner, the eight-volume encyclopedia Geschichtliche Grundbegriffe (Basic Concepts in History: A Historical Dictionary of Political and Social Language in Germany.
[7] This overcame religious civil war and gave rise to the early modern, centralized state, which had a clear, narrow and authoritarian conception of politics as the monopolization of legitimate violence and the guaranteeing of obedience, security and order.
In fact, for Koselleck modern philosophies were a form of a secularized version of eschatology: that is, theological prophecies of future salvation, an interpretation he adopted from Karl Löwith, his teacher at Heidelberg University.