アッツ島沖海戦
Vice Admiral Boshirō Hosogaya, commander of the 5th Fleet and the Northern Area Force, put in an embarrassing performance in the Battle of the Komandorski Islands on 26 March 1943 while in command of a task force escorting a convoy bringing reinforcements to the Japanese garrison on Kiska in the Aleutian Islands, sending the convoy back to port and withdrawing in the face of a smaller United States Navy force. As a result, Hosogaya was relieved of command on 31 March 1943, and Kawase was placed in charge of the 5th Fleet and the Northern Area Force the following day with his headquarters at Paramushiro in the Kurile Islands.