In the third part of our Countdown to D-Day officer bios, Peter Margaritis reveals the life and legacy of Ōshima, a Japanese diplomat and staunch Nazi supporter.
58-year old Baron Hiroshi Ōshima came from a wealthy Japanese samurai family. His father had served as the Japanese Minister of War in World War I. Hiroshi became a professional soldier and as such, was given the position of assistant military attaché to the German Weiman Republic, before returning to Japan in 1926.
In 1934, Col. Ōshima was appointed the Japanese military attaché and ambassador to the new Third Reich and promoted to major general the next year. A staunch Nazi supporter (William Shirer, in The Rise and Fall of the Third Reich, wrote that Ōshima “is more Nazi than the Nazis”) and a personal friend of Foreign Minister Joachim von Ribbentrop, Ōshima quickly became a favourite of Hitler, and as such, he was given access to many key conferences and made privy to many strategic meetings and conversations with the Führer and the German High Command. Because the United States had in 1940 cracked the Japanese diplomatic Purple Code that Ōshima used to encrypt his detailed dispatches to Japan (a code the Germans warned him on several occasions as being unreliable), the Allies were able to intercept and read to most of the messages the ambassador radioed to Japan, and by extension, often to many of the German High Command plans and their positions on military situations.
Interesting points about Ōshima:
- Mistakenly predicted that Great Britain would fall before the end of 1941.
- Played a vital part in Japan joining the Tripartite Pact in the fall of 1940.
- Tried to use Russian agents to assassinate Joseph Stalin.
- Was one of only fifteen foreign recipients of the German Grand Cross of the Order of the German Eagle in Gold (Grosskreuz des Deutschen Adlerordens)
Between 1941 and 1945, nearly all of Ōshima’s dispatches—almost 1,500—were intercepted by the Allies, and most were decoded, including some 600 in just 1944. Taken into custody by the Americans in May 1945, he was later found guilty of war crimes and sentenced to life but was paroled in 1955. Ironically, he died ironically exactly 31 years after D-Day in Tokyo. Ōshima never found out how much his war dispatches had helped Allied intelligence.
Perhaps General George C. Marshall said it best, referring to Ōshima as “our main basis of information regarding Hitler’s intentions in Europe.”
Ōshima and his role in the defence of the Atlantic Wall is explored in the new book, Countdown to D-Day, due to be released June 2019.
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