Large numbers of Allied POWs were taken as the Nazis stormed across Europe. Hundreds of thousands of French soldiers were taken to Germany and put into forced labor camps. By 1945 the majority of forced laborers in Germany were French. Two hundred thousand British and Dominion troops were captured in France, Greece, Crete and North Africa. Thousands of Americans were shot down over Germany or taken in combat in Italy. They were all sent to camps in Germany.
When Germany invaded the Soviet Union, the huge encirclements of 1941 swallowed whole Russian army groups. Some five million Soviets went into captivity, including large numbers of Russian women. Only one out five would come home again.
Huge numbers of Allied POWs were captured in the Pacific between December 1941 and May 1942. After the fall of the Philippines, most Allied POWs were killed in the field rather than captured because the Japanese were cut off from relief.
Nevertheless, the Western Allied POWs under the Nazis fared much better than the POWs in the Pacific. While the Soviet and German soldiers died in huge numbers on the Eastern front, only 25% of Allied POWs died in German hands. In Japanese hands, 51% of Allied POWs died of all causes.
Once Japanese soldiers were captured, they were reported as dead to their families and many Japanese POWs chose to aid the Allied effort. Prisoners provided the Allies with important information, sometimes directing bombers against their former comrades.