 However, unlike the IJN 5th Fleet, the 4th Fleet was never in actual combat.On November 15, 1939, the 4th Fleet was absorbed into the 3rd China Expeditionary Fleet under the overall aegis of the China Area Fleet.Although most of its ships were released for service with the Combined Fleet in the Pacific War a year later, most of the staff for the 4th Fleet remained in China, and were assigned to the Tsingtao Base Force for the duration of the war.