From May 1936 until shortly before the end of his days in the Dachau concentration camp in 1945, the writer Friedrich Reck kept a diary in which he recorded his impressions of the National Socialist regime. This is an exceptional document in that it illustrates the rejection that Nazi ideology aroused in certain conservative circles, such as those frequented by the author himself. Particularly significant in this scathing and exasperated critique are those passages in which he describes his regret at not having been able to kill Hitler when he was close. Diary of a Man in Despair had numerous editions in Germany—the first dating back to 1947—and in various European countries. However, it was not until 1994 that the diary was published, which, thanks to the research of historian Christine Zeile, is considered the definitive edition: this is the one used for the first publication of the book in Spanish.