Clue is this guy -
船川海事部副長 諸井喜代治 - Deputy General Manager of Funakawa Maritime Division Kiyoji Moroi
He was a prominent person in the postwar Akita Prefecture.
Akita Pref. held the 17th Infantry Regiment of IJA.
This regiment was deployed in Philippines in July 1944 but ended the war with few chances to fight due to food/munition shortage in the mountains.
The original flag owner was 管原與治郎 (Yojiro Sugawara) with age estimated around 30 as he was enlisted as a corporal.
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