From The Anguish of Surrender: Japanese POWs of World War II, by Ulrich Straus (U. Washington Press, 2005), pp. 196-199:
Allied forces also captured roughly ten thousand ethnic Koreans and Taiwanese working for the Japanese. Although some Koreans were integral members of the Japanese armed forces, most had either volunteered for or been drafted into labor battalions ordered into combat only when the tactical situation became desperate. Then they became little more than cannon fodder, along with the Japanese soldiers. The Koreans and Taiwanese in the labor battalions, however, did not share the Japanese preference for death over capture and surrendered to Allied forces in droves whenever it became feasible to do so. It was Allied policy to separate out captured Koreans and Taiwanese, assigning each group to its own enclosure. Cowra, in Australia, was the exception, in that it kept Japanese and the few ethnic Korean officers in the same enclosure. Koreans and Taiwanese were not imprisoned any further east than Hawaii, and many remained in the general area of their capture. Once the war ended, they were among the earliest to be repatriated.
There was never much love lost between the Japanese and Koreans, and imprisonment did nothing to change that fact. Japanese POWs felt genuinely appalled, almost betrayed, to discover that the Koreans thought of themselves as victors once the war ended and looked down on the Japanese. Some Japanese POWs, including Takahashi Shigeru, realized that Japan had discriminated against Koreans and Taiwanese and that the Koreans’ gleeful attitude when Japan lost therefore “could not be helped.” In the few instances when Japanese were erroneously placed into an enclosure with Koreans, they were beaten up in revenge for earlier treatment at the hands of their colonial masters.
Most ethnic Koreans who had served as integral members of the Japanese military chose to maintain their Japanese identity in the prison camps. They may well have feared the wrath of fellow Koreans who had been pressed into the labor battalions and believed they would be more secure in the Japanese section. One of the reports from Cowra noted that Koreans caused no trouble for the Australians, except for a small minority who were “very pro-Japanese.” This element compelled the rest to face east and bow reverentially after every roll call. When fellow Koreans disregarded this courtesy to the emperor, they were manhandled.
Taiwanese hostility toward the Japanese POWs was substantially less than that of the Koreans. American comments about Taiwanese prisoners, who never created problems, were entirely positive. When interrogated about possible American landing sites on Taiwan, they were uniformly eager to provide all the information they had.
On Okinawa the American army split up Japanese POWs in yet another way, separating not only Japanese and Koreans but Okinawans as well. Initially somewhat resistant to the idea of being distinguished from Japanese, Yamada Yuko soon became rather pleased to be called Okinawan rather than the pejorative “Jap” that was in common usages by Americans during the war. Given the Okinawans’ widespread disillusionment with the Japanese military, especially its ruthless treatment of tens of thousands of civilians needlessly exposed to the hazards of war, it is hardly surprising that Okinawans relished this separate treatment, a difference manifested in a number of ways. Noting that Americans were eager to obtain Japanese swords as souvenirs, Okinawan POWs volunteered to help them find some. On several occasions they were even allowed to leave the prison camp without guards to search for souvenirs. Such complete trust was so greatly appreciated that the Okinawans could not think of betraying it. Nevertheless, when news of Japan’s defeat filtered into the Yaka stockade, Yamada felt humiliation, and when the Koreans held their victory celebration, he thought that his own feelings were no different from the feelings of those who came from other Japanese prefectures.