How Japan Helped the Allies Spy on Hitler

Baron Oshima & Adolph Hitler

Throughout the Second World War, the Allies tried to spy on Hitler and his generals. They went to extraordinary lengths to understand what the Führer was thinking, using intercepted messages, intelligence from inside Germany, and the advanced decryption facilities at Bletchley Park.

Ironically, some of their best intelligence on Hitler’s thinking came not from spying on the Germans but on their allies, the Japanese.

The groundwork for Baron Hiroshi Oshima’s role as an intelligence source was laid in 1934 when he arrived in Berlin to act as Japanese Military Attaché. An officer and a diplomat, Oshima quickly established good relationships with German officers and members of the Nazi party, who had risen to power in Germany the year before.

Oshima’s political philosophy was a good fit with that of the Nazis. He soon gained the ear of Hitler, becoming the Führer’s favored representative of Japan.