Original Item: Only One Available. Incredibly rare original August 25, 1945 publication of data on Northern Japan, issued to Officer’s within the IX Corps in order to plan and prepare for the potential invasion of Japan. The Invasion of Northern Japan by IX Corps was scrapped first when the Invasion of Hokkaido was proposed to be conducted by the Soviets, and second, naturally after the bombings of Hiroshima and Nagasaki with the Atomic Bomb.

This packet contains an incredible amount of intelligence information compiled by the G-2 (Intelligence) section of the IX Corps. Multiple detailed maps and aerial photographs (all marked “confidential”) highlighting Japanese unit positions, landmarks, military bases, airfields, etc. In addition to the maps and aerial photographs is a packet of 74 pages of written intelligence, consisting of information on military units in the area, tidal patterns, industries in the area, compositions of local military units, etc. an incredible wealth of knowledge. It is a staggering amount of information that was accumulated in preparation for a large military operation that never happened. Packet shows obvious wear from handling and age over the years. Packet measures  13.5” x 9”.

Operation Downfall was the proposed Allied plan for the invasion of the Japanese home islands near the end of World War II. The planned operation was canceled when Japan surrendered following the atomic bombings of Hiroshima and Nagasaki, the Soviet declaration of war and the invasion of Manchuria. The operation had two parts: Operation Olympic and Operation Coronet. Set to begin in November 1945, Operation Olympic was intended to capture the southern third of the southernmost main Japanese island, Kyūshū, with the recently captured island of Okinawa to be used as a staging area. In early 1946 would come Operation Coronet, the planned invasion of the Kantō Plain, near Tokyo, on the main Japanese island of Honshu. Airbases on Kyūshū captured in Operation Olympic would allow land-based air support for Operation Coronet. If Downfall had taken place, it would have been the largest amphibious operation in history.

Japan's geography made this invasion plan quite obvious to the Japanese as well; they were able to accurately predict the Allied invasion plans and thus adjust their defensive plan, Operation Ketsugō, accordingly. The Japanese planned an all-out defense of Kyūshū, with little left in reserve for any subsequent defense operations. Casualty predictions varied widely, but were extremely high. Depending on the degree to which Japanese civilians would have resisted the invasion, estimates ran up into the millions for Allied casualties.