From Storm Clouds over the Pacific, 1931–1941, by Peter Harmsen (War in the Far East, Book 1; Casemate, 2018), Kindle pp. 6-7:
In late summer 1939, a 22-year-old man in the uniform of a Wehrmacht officer was on his way to Germany’s border with Poland. His mission was to attach himself to a German division as an observer during the invasion that was only days away. The young man must have attracted considerable attention since his features were anything but Aryan. His name was Chiang Wei-kuo, and he was the adopted son of China’s leader, Chiang Kai-shek. For the past two years he had undergone advanced military training at the War Academy in the south German city of Munich. In that capacity, he had even taken part in Germany’s peaceful occupation of Austria in March 1938.
Chiang Wei-kuo’s story was a reflection of how close Sino-German ties had grown in the 1930s, as Germany’s resurgent armament industry was exporting vast quantities of military equipment to the Nationalist Chinese regime, whose efforts at building up a large modern army were also assisted by a corps of experienced German advisors. The assistance had proved particularly useful since 1937, after full-scale war broke out between China and Japan. By 1939, however, Germany was growing friendlier with Japan and was busy distancing itself from Chiang’s regime. As a result, Chiang Wei-kuo’s presence was beginning to appear out of place, and when he passed through Berlin en route to the Polish border and paid a visit to the Chinese embassy, he received new orders: he was to travel to the United States for military training there.
Consequently, by the time German panzers rolled into Poland in the early hours of September 1, Chiang was already on a ship bound for America, which was emerging as an important new ally for China. He would soon commence studies at the Armored Force Center, Fort Knox, before returning home three years later, his brain filled with the latest military knowledge. He was not the only one in his family to travel widely. His stepbrother Chiang Ching-kuo had spent 12 years in the Soviet Union. He had a Belarusian wife and even a Russian name, Nikolai Vladimirovich Elizarov.
The two stepbrothers formed just a corner of a corner in the immensely complex web of relations and interactions that characterized Chinese and Asian politics and society during the 1930s, the decade that saw the Sino-Japanese War flare up and, little by little, set in motion events which would eventually lead to Japan’s conflict with an array of Western powers. What the Chiangs do exemplify, however, is the extent to which the war in the Asia Pacific was, right from its earliest origins, a global affair, involving both indigenous actors and actors from thousands of miles away.