Based on new documents, especially von Siebold's correspondence, written advice, and draft treaties that were placed in the public domain by the Brandenstein-Zeppelin family in 2002, the author argues that such is their significance a full reevaluation of von Siebold's role in the successful opening of Japan in the 1850s is now justified, and that new perspectives emerge in relation to twentieth-century scholarship that was dominated by the exploits of Commodore Matthew Perry and the roles of Townsend Harris and Rutherford Alcock. The author also accepts that even in light of these new primary sources, von Siebold remains a controversial figure whose role was more often than not "tinged with considerable selfish aspirations and a belief in his personal infallibility.