A small amount of information about the lives of those German POWs who chose to remain in Japan can be found in an account by Mahon Murphy of Trinity College Dublin, "Brücken, Beethoven und Baumkuchen: German and Austro-Hungarian Prisoners of War and the Japanese Home Front," published as a chapter in Bürgschwentner, Egger and Barth-Scalmani, Other Fronts, Other Wars: First World War Studies on the Eve of the Centennial, by Brill in 2014.

Murphy points out that 4,800 POWs were transported to Japan, and they remained interned for a long time – until early in 1921. This gave them more time to learn the local language (for the most part they were kept in less than arduous conditions, often near major population centres, and there seem to be many photos showing them mixing with their captors and even local people). Assimilation does not seem to have been a significant goal of most prisoners; they insisted, for example, on a European style diet heavy on beef, cabbage, cheese and potatoes, which were difficult for the Japanese to supply; the only cattle and milk available had to be brought down from Hokkaido. Eventually prisoners were given the chance to farm their own cattle. Murphy adds, however, that "there was much interest" in the prisoners and that locals would gather to hear the "red haired devils" sing drunken songs within the confines of their camps. At Hiroshima, a local Japanese football team was put together to play Japan's "first international" soccer match against the POWs. Exhibitions of German culture were also organised for the benefit of Japanese visitors to the camps - Murphy's chapter title refers to a first-ever performance in Japan of Beethoven's Ninth Symphony (June 1918).

Local response seems to have been good natured curiosity - POWs were treated very much better in Japan in WWI than they would be in WWII. Several camps organised German food fairs which offered the first opportunity for Jaoanese to sample tomatoes, cured bacon, and German style beer.

Of the Germans who chose to remain in Japan after release, the most prominent was Karl Jucheim, who had run a sweet shop in Tsingtao (Qingdao) before the war, and used that expertise to set up what became a brand-name desert business selling traditional German baumkuchen - pastry desserts. These were a significant success, and his baumkuchen can still be found on sale in Japan today. Jucheim set up his business in Yokohama, then moved to Kobe after the great earthquake of 1923. He died in August 1945.

Less is known of the other 177 prisoners who stayed on,but several seem to have followed similar career paths. Hermann Wolschke set up a sausage factory. Hermann Ketel and August Lohmeyer both opened European style restaurants in Tokyo – the former lasted until 2004 and the latter is still doing business under Japanese ownership.Others became German teachers or worked in cultural relations.

Incidentally, Murphy draws much of his information from the Tsingtao War German Prisoners Research Society (that's a translation from the Japanese), which apparently publishes an annual journal – so I suspect there is more to find out about these unusual cultural migrants.