旅順港閉塞作戦
The Russian naval base was seized by Japan after the Battle of Port Arthur in August 1904 and was proclaimed the . However, it lacked the shipyards, armories and the training facilities associated with other naval districts, (for which it relied on Sasebo Naval District). Tasked primarily with coastal patrols of the Liaodong Peninsula and control of the strategic seaward approaches to Tianjin and Beijing, it was regarded as a prestigious posting, with its commander receiving his commission directly from the Emperor.