Ōminato Guard District
Japan entered World War II on 7 December 1941 – 8 December 1941 across the International Date Line in Japan – with its attack on Pearl Harbor, Hawaii. Soon thereafter, Kawase took command of the 3rd China Expeditionary Fleet – responsible for operations off northern China, in the Bohai Gulf and off Tsingtao – on 26 December 1941. He transferred to the Navy General Staff in Tokyo on 10 April 1942, then on 15 September 1942 became commander of the Ōminato Guard District, the major Imperial Japanese Navy base in northern Honshu, responsible for control of Tsugaru Strait and patrols along the coasts of Hokkaidō and Karafuto and in the Kurile Islands.