Military Intelligence Service

The Military Intelligence Service (Japanese: 陸軍情報部) was a World War II U.S. military unit consisting of two branches, the Japanese American Unit described here and the German-Austrian Unit based at Camp Ritchie, described partly in Ritchie Boys. The unit described here was primarily composed of Nisei (second-generation Japanese Americans) who were trained as linguists. Graduates of the MIS language school (MISLS) were attached to other military units to provide translation, interpretation, and interrogation services.

The MISLS (initially known as the Fourth Army Intelligence School) began operation in November 1941, about a month before the Japanese bombed Pearl Harbor. The school initially operated at Crissy Field in San Francisco, but moved to Savage, Minnesota in 1942. There were more than 6000 graduates of MISLS.

The first MISLS students came from the army, but later students were also recruited from Japanese internment camps. MIS members attached to the joint Australian/American Allied Translator and Interpreter Section were instrumental in deciphering and translating the Z plan, an important captured document that described Japanese plans for a counterattack in the central pacific.

In March 1942, the Military Intelligence Division was reorganized as the Military Intelligence Service (MIS). Originally comprising just 26 people, 16 of them officers, it was quickly expanded to include 342 officers and 1,000 enlisted men and civilians. It was tasked with collecting, analyzing, and disseminating intelligence. Initially it included:

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