Fort McCoy housed many prisoners of war and is known to have held the most Japanese POWs during the war. About 3,000 German, 2,700 Japanese, and 500 Korean prisoners of war were held there. There were many other places that these prisoners were housed. President Franklin D. Roosevelt issued an executive order titled Order 9066 that brought these prisoners into the different states and away from the coasts. The first Japanese prisoner of war to enter the camp was captured at Pearl Harbor.