The Japanese Imperial Combined Fleet in the post-Washington Naval Conference era

The research to date on the topic of the aftermath of the Washington Naval Conference of 1921-22 and its disarmament treaty has focused mainly on such issues as the independent authority of the supreme commander, the independence of the Naval General Staff and the choice of Naval cabinet ministers, but has yet to fully describe and analyze the Japanese Imperial Navy’s actual response to the provisions of the treaty. The present article takes up the treaty’s influence on naval operations by focusing on the permanent deployment of the Combined Fleet and subsequent changes in its military role and mission.<br> It has been thought that the organization of the Imperial Navy was characterized by a dual division of labor between the Naval Ministry in military administrative affairs and the General Staff in military command affairs ; however, it would be more accurate to characterize that structure as consisting of high commanders of Naval bureaus---the Naval Minister, the Fleet and naval installation general staffs, and the commanders in chief---all acting under juxtaposing administrative and supreme command authorities, with the Fleet and naval installation commanders in chief assuming leadership over the chain of command in the field.<br> The Imperial Navy’s response to the disarmament treaty was to adopt policies aiming at maximizing troop excellence, one part of which was to permanently deploy the Combined Fleet, resulting in the major Naval troop forces being merged into the Fleet and the peacetime authority and role of the Fleet commander in chief being clearly defined. It was in this way that the Combined Fleet was transformed from an organization for assuming unified command in emergency situations to a day-to-day organ assuming leadership over naval operations and management of troops in the field.<br> As the threat of war became more and more imminent, the scale of the Combined Fleet was greatly expanded, resulting in a division between the Fleet command and the admiralty commanding the Fleet’s squadrons=battleship divisions, with the Fleet command situated in the rear taking responsibility for strategic planning. This change in the role of the Fleet command to a general staff function not only posed problems in the Navy’s centralized operations, but also caused a gap in military spirit between the command and its squadron commanders. As a result, Naval leadership on the battlefield would be determined in the rear by Imperial Naval Headquarters, orders sent to the Fleet command, then transmitted to squadron commanders for implementation in the field, forming a centripetal threefold structure, indicative of how the complete change in character and role of the Combined Fleet after the signing of the Washington Treaty greatly influ-enced the operations of the Imperial Navy as a whole.