Imperial Japanese Navy General Staff

The Imperial Japanese Navy General Staff (軍令部, Gunreibu^?) was the highest organ within the Imperial Japanese Navy. In charge of planning and operations, it was headed by an Admiral headquartered in Tokyo.

Created in 1893, the Navy General Staff took over operational (as opposed to administrative) authority over the Imperial Japanese Navy from the Navy Ministry. It was responsible for the planning and execution of national defense strategy. Through the Imperial General Headquarters it reported directly to the Emperor, not to the Prime Minister, Diet of Japan or even the Navy Ministry. It was always headed by an admiral on active duty, and was based in Tokyo.

"The ministry was responsible for the naval budget, ship construction, weapons procurement, personnel, relations with the Diet and the cabinet and broad matters of naval policy. The General Staff directed the operations of the fleet and the preparation of war plans".

After the Washington Naval Conference of 1921-22, where Japan agreed to keep the size of its fleet smaller than that of the United Kingdom and the United States, the Imperial Japanese Navy became divided into the mutually hostile Fleet Faction and Treaty Faction political cliques. The Navy Ministry tended to be pro-Treaty Faction and was anxious to maintain the Anglo-Japanese Alliance. However the Navy General Staff came to be dominated by the Fleet faction, and gradually gained ascendancy in the 1930s with increasing Japanese militarism.The Navy General Staff pushed through the attack on Pearl Harbor against the wishes of the more diplomatic Navy Ministry.

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