Since Karl Haushofer published Dai Nihon in 1913, his views have been interpreted in many different ways. Therefore, the first question to ask about any new book on Haushofer must be whether it takes into account earlier research and whether it offers new insights. Holger Herwig's acknowledgments reveal his contacts with the Haushofer family and research activities at various archives and thus raise high expectations in this regard. Yet, despite the fact that he mentions “a veritable mountain of primary and secondary works” (xvii), he not only ignores most recent research but also does not offer many new insights.

Most of the information Herwig presents as new has been available for years. He ignores many relevant German publications by Tilde Bayer (1995), Henning Heske (1995), Rainer Sprengel (1996), Rudolf Gottschlich (1998), Christian W. Spang (2000, 2001, 2003, 2013), Ernst Haiger et al. (2002), Heike Wolter (2003), and Cornelia Lüdecke (2004), and he also overlooks important articles by Mark Bassin (1987) or Heske and Rolf Wesche (1988) published in English.

Herwig's book resembles an extended essay rather than an academic monograph. In his introduction, he admits that “the approach [of his book is] speculative at times” (xvi), which he explains by a lack of primary sources, mentioning that “the personal diaries of both Karl and Albrecht Haushofer were destroyed or lost” (xvi). Yet, this claim is not true. Although most of Albrecht Haushofer's diaries are lost, many of Karl Haushofer's diaries are available at the Federal Archive in Koblenz, and only those covering the years 1926 to 1930 are missing. Furthermore, many of Martha Haushofer's diaries are available in Koblenz as well. Finally, a 150-page travel diary, written by Albrecht Haushofer in the summer and autumn of 1937, has been saved by the family.

Instead of a regular reference section, the book features a six-page “Note on Sources” (251–256), in which only three publications that have appeared since 2000 are mentioned. Even works frequently referred to in Herwig's own endnotes (such as Ian Kershaw's famous Hitler biography) are not listed, just like all the above mentioned publications of the years 1987-2013. Instead, Herwig frequently refers to Bruno Hipler's 1996 book as “recent” (xv) or “most recent” (xii), even though it was published twenty years prior to The Demon of Geopolitics.

Herwig's book offers a short German-English glossary (249). Yet, several of the translations are not very convincing. For example, Herwig's tendency to translate “-denken” as “orientation” is at least unusual; “thinking” would be much more natural. Also, Herwig's translation of “Volksboden” is far too short and therefore unclear. Various additions are necessary to clarify the term: “regions [beyond Germany's borders] where [ethnic] Germans were still living [after WWI].”

In his endnotes, Herwig often abbreviates his references, which would be acceptable only if the book included a traditional reference section. A look at the first endnote (221) serves as a case in point. Herwig writes, “Cited in Karl Haushofer, 2:568-69.” Readers can hardly be expected to know that this refers to pages 568–569 of Hans-Adolf Jacobsen, Karl Haushofer—Leben und Werk, vol. 2 (Boppard, Germany: Boldt, 1979).

Even simple biographic facts are sometimes wrong. Although Karl Haushofer had only one sister and one brother, Herwig invents a third brother (2). He also wrongly points out that Martha had agreed to stay behind in Bavaria after her husband was chosen as the first Bavarian military observer to Japan. In fact, there is no doubt that Martha was the driving force behind Karl's application because she was far more interested in going to Asia than he was (Jacobsen 1979, vol. 1, 95–97). Herwig claims that that Haushofers employed eight people in Japan (20), while in fact, they hired and paid only four aides: a cook and his wife, a houseboy, and a stable boy. Equally wrong is Herwig's claim that Haushofer “throughout the 1920s had supplied the [German] army with secret foreign policy reports” (147). Although Herwig's source (Heske 1987, 39) mentions “several years,” in fact, the latest research (Spang 2013, 321–325) has shown that Haushofer wrote these reports most likely only for one year.

Throughout the book, there are quotes that either lack any reference or feature a mistaken reference, for example chapter VI, note 6 (Herwig says what Jacobsen referred to but not where Jacobsen does so); chapter VI, note 16 (Herwig refers to Jacobsen 1979, vol. 1, 1–2, but there are no numbered pages 1–2 in vol. 1 of that book); or conclusion, note 34 (Herwig refers to pages 94–95; correct is 394–395).

In a footnote on page 122, Herwig mentions “Haushofer's insistence” that only “previously published articles” were reprinted in the anthology Bausteine der Geopolitik (recte: Bausteine zur Geopolitik). A simple look at the last page of the Bausteine (349) is enough to show that this claim is wrong: here, the editors of the volume explain that the book contains new as well as extensively revised articles. When Herwig correctly elaborates on Haushofer's anti-democratic leanings, he mentions Haushofer's criticism of “a Reichstag consisting of thirty-seven self-serving parties” (138). It remains completely unclear what Herwig had in mind when he wrote this. A look at various Reichstag election results between June 1920 and March 1933 shows that an average of thirteen parties had seats in the Reichstag.

Further examples show Herwig's difficulty to fully grasp the Japan-related aspects of Haushofer's career. In his introduction (xv), Herwig makes Yamagata Aritomo, one of the most famous leaders of Meiji Japan (1868–1912), “a member of the powerful Chōshū daimyo house.” In fact, Yamagata was a lower ranked samurai without any direct connection with the Mori clan, the local dynasty. On page 170, Herwig calls Itō Hirobumi, another famous leader of Meiji Japan “general,” which is incorrect. Furthermore, Herwig's translations (157) of the Japanese codenames that were used within the Haushofer family for various Nazi leaders such as Adolf Hitler (“O-Daijin”) or Joachim von Ribbentrop (“Taish[i]kan”) are wrong. The proper translation of “(o-)daijin” would be “government minister.” According to Herwig, the term means “a rich man who uses money generously.” “Taishi” should be translated as “ambassador” while “kan” could stand either for “building” or “any kind of bureaucrat or official” (see for example “shidōkyōkan” = “academic advisor”). Yet, Herwig translates the term as “court official.”

On pages 162–163, Herwig refers to the last encounter between Haushofer and Hitler, ignoring again important details published elsewhere (Spang 2013, 444–446). According to Herwig, Haushofer “referred to that day as the final and irreparable break with Hitler” (163), which is not wrong, but Herwig's statement that Haushofer did so “for the rest of his life” (163) is misleading. In fact, Haushofer never mentioned this episode until the end of World War II was approaching. Only then did he start to talk about it, that is, at a point when this supposedly “final and irreparable break with Hitler” seemed to offer a way to avoid sharing in the responsibility for Nazi crimes (Spang 2013, 372).

Anyone who knows the full story of Karl Haushofer will notice many of Herwig's mistakes or misinterpretations, but the general reader will take them as facts, which makes Herwig's book at the very least problematic. In various ways, it is a retrograde step compared with most of the latest Haushofer-related research, which Herwig seems to have chosen to ignore. Overall, the narrative gets more reliable and conclusive the farther the story gets away from Haushofer. For a book that allegedly informs the reader of how Karl Haushofer “educated” Hitler and Hess, this is not exactly a recommendation.