Nisei Japanese American

Americans of Japanese ancestry living in the western United States, including the Nisei were, forcibly interned with their parents and children (the Sansei Japanese Americans) during WWII.

Most Japanese Americans who fought in WWII were Nisei. The 100th Infantry Battalion and 442nd Regimental Combat Team, fighting in the European theatre, became the most decorated unit in U.S. military history for its size and length of service.

Americans of Japanese ancestry were generally forbidden to fight in a combat role the Pacific theatre. No such limitations were placed on Americans of German or Italian ancestry who fought against the Axis Powers in Europe. However, about 6,000 Nisei did serve in the Military Intelligence Service (MIS) as linguists and in other non-combative roles, interpreting captured enemy documents and interrogating POWs. MIS linguists translated Japanese documents known as the "Z Plan," which contained Japan's counterattack strategy in the Central Pacific. This information led to Allied victories at "The Great Marianas Turkey Shoot," in which the Japanese lost most of their carrier planes, and the Battle of Leyte Gulf in the Philippines. An MIS radio operator intercepted a message describing Admiral Isoroku Yamamoto's flight plans, which led to P-38s downing his plane over the Solomon Islands. General Douglas MacArthur stated, "Never in military history did an army know so much about the enemy prior to actual engagement." General Charles Willoughby, MacArthur's intelligence chief, said, "The Nisei saved countless Allied lives and shortened the war by two years."