Hashimoto served as commander of various destroyer task forces through the 1930s, winning promotion to captain in 1935.

He was Chief of Staff of the Ryojun Guard District from 1937 to 1939, and assumed command of the cruiser Chikuma from 1939 to 1940 and battleship Hyūga from 1940 to 1941.

[1] At the time of the attack on Pearl Harbor, Hashimoto was in command of the 3rd Destroyer Flotilla,[1] covering landings of Japanese forces in Malaya.

In January 1943, Hashimoto's destroyers participated in "Operation Ke", and successfully evacuated 11,700 surviving Japanese troops from Guadalcanal.

From March to October 1943, Hashimoto received a shore assignment and became Commandant of the Torpedo School.