The German Duden lexicon defines "Vergangenheitsbewältigung" as "public debate within a country on a problematic period of its recent history—in Germany on National Socialism, in particular"—where "problematic" refers to traumatic events that raise sensitive questions of collective culpability. In Germany, and originally, the term refers to embarrassment about and often remorse for Germans' complicity in the war crimes of the Wehrmacht, Holocaust, and related events of the early and mid-20th century, including World War II. In this sense, the word can refer to the psychological process of denazification. With the accession of the former German Democratic Republic into the current Federal Republic of Germany in the reunification of 1990 and the fall of the Soviet Union in 1991, "Vergangenheitsbewältigung" can also refer to coming to terms with the excesses and human rights abuses associated with that former one-party state.