 In order to adequately mix his fictional characters with historical figures, Hughes relied on firsthand accounts and family papers from German relatives and friends, including distant relation Baroness Pia von Aretin (whom he acknowledges in the 1961 US edition of the novel) and Helene Hanfstaengl, who had been a friend of Hitler’s in the early 1920s.Hughes also gives an explanation for his unconventional description of the Munich Putsch saying that his narrative "is based on a vivid contemporary account by an actual Nazi participant, a Major Goetz.This account was contained in a letter to a friend dated 26th November, 1923, which some weeks later found its way into the German press."