BOUGAINVILLE OPERATIONS - by Sus Toyoda
Ourstory began in December 1943 when we (the US Army 173rd Japanese Language Detachment) flew from Commander, South Pacific (COMSOPAC), Noumea, New Caledonia, to Bougainville to relieve Dye Ogata and his team - they had seen action with the Ohio 37th Infantry Division through the New Hebrides and New Georgia campaigns. The 37th and the Americal Infantry Divisions (under XIVth Corps and the Australian 3rd Division) defended a perimeter containing, the Piva bomber and fighter airstrips from which air attacks were mounted against Rabaul, a Japanese stronghold to the north. Confronting this perimeter defense was the infamous Japanese 6th Infantry Division (known for the Rape of Nanking), an independent mixed brigade and sundry other troops. The 6th was composed of the 13th Regiment from Kumamoto, the 23rd from Kagoshima and the 45th from Miyazaki.
Our language detachment (attached to G-2, 37th Infantry Division) was composed of Captain Gilbert B. Ayres, Lieutenant Jerome Davis, Joe Yoshiwara, Yukio Kawamoto, Seian Hokama, Maxie Sakamoto, Keiji Fujii, Tad Uriu and myself. During Japanese attacks on our perimeter defenses, this hard working, self-sacrificing group worked tirelessly from early morning until late at night. Sixteen to 17-hour days were commonplace during March of 1944.
When time and opportunity presented itself we took advantage of it to give orientation lectures to the front-line troops. We impressed upon them that although we looked Japanese, we were the good guys. We stressed how, with their assistance, we could help each other in fighting the enemy. We told them of the importance of captured documents detailing sources such as the enemy order of battle. Captured equipment could provide a clue as to the state of their supply system, and prisoners were potential gold mines for information on current combat situations. Infantrymen were cautioned never to take unnecessary chances to capture a prisoner - it just wasn't worth risking one's life. However, if they were successful in capturing a prisoner, they were asked to extend humane treatment, such as, giving water, cigarettes or food; and if wounded, to give first aid. The hope was that the prisoner would respond favorably and could make our interrogation more fruitful. To further establish rapport with our own troops, after the lectures we played volleyball so they could become familiar with us, thereby avoid any untoward incidents since we were fighting for the same cause.
Our first opportunity came in late February 1944. One of the patrols from the l48th Infantry Regiment* engaged a Japanese patrol in a fire-fight which resulted in a captured prisoner. A language detachment member, detailed to the 148th conducted a preliminary interrogation of the prisoner for immediate tactical information. He was then sent back to Division Headquarters where we could conduct a more thorough (our first) interrogation. We were fully expecting him to be reluctant and uncooperative. Much to our surprise the prisoner was ready and willing to tell us whatever he knew. Perhaps itwas the result of the good treatment he received from the time of capture to his delivery to division headquarters. We learned that he was a member of the 45th Regiment of the 4th Division; that he was on a probing patrol to detect weak spots in our perimeter defense; became engaged in a fire-fight and had been captured. He had heard this increased patrol activity was in preparation for a regimental attack on our defenses. He was not privy to the date of this general attack but had heard it would be soon. We were aware that the Japanese military was prone to carrying out general attacks on Japanese holidays and the nearest one was March 10, Japan's Army Day. This probability was immediately communicated to the Division Commanding General, Robert S. Beightler, his G-2 and to the XIVth Corps.
In the ensuing two weeks the perimeter defenses were doubled and tripled in anticipation of the March 10 attack. Sure enough, the 45th Infantry attacked as we had anticipated; but our defenses were so formidable that repeated mass attacks resulted in the decimation of the Japanese regiment of approximately 3000 men. Our infantry reported witnessing the Japanese charging against our withering machine gun fire, being cut down wave after wave, and their bodies stacking up like cordwood in front of our pillboxes. They said it was like shooting fish in a barrel; but the relentless determination of the enemy to carry out the repeated attacks against overwhelming odds was unbelievable. They shuddered to think what might have happened had they not been forewarned. All that remained was the mass burial of the fallen Japanese soldiers.
There was a lull in the fighting highlighted by probing enemy patrols in the sector defended by our 129th Infantry Regiment. From captured documents we had determined that the 23rd Infantry Regiment of the 6th Division was facing our 129th One reinforced enemy patrol temporarily breached our defenses and instead of strengthening their position, the patrol elected to sit down and eat their breakfast! This strange maneuver could only be explained by the happenstance that their patrol leader had been killed during the breaching action. In the meantime our troops had reorganized, returned and proceeded to annihilate the breakfast-eating enemy patrol.
During the late afternoon of 23 March a jeep trailer load of captured documents was delivered to us by the 129th S-2 (Intelligence). We immediately commenced screening the documents, and to my great surprise, I found a tactical map of the 23rd Infantry. It was like hitting the jackpot! It was smeared with blood and presumably recovered from the body of a patrol leader. It was a tactical map detailing a regimental attack on our perimeter defense, showing the assembly area, the line of departure, the line of attack, but without a date nor time of attack The Japanese had been probing our lines every other night starting about 2000 hours (8:00 PM). Since the map and documents had been captured two nights previously, it was reasoned that the 23rd Infantry's attack on the 129th was planned to begin about 2000 hours that very night. As luck would have it, the scale of the map was identical to our tactical map. This was indeed a bonanza! An overlay with all pertinent information was being prepared for General Beightler when he requested that I give him a briefing. I later learned that the General immediately called XIVth Corps with the information and it was decided that the artilleries of the 37th Americal Divisions and the XIVth Corps would zero in on the 23rd Regiment's assembly area commencing at 1700 hours. Reportedly, the resulting barrage was the heaviest in the Pacific Theater. All night long we heard the shells whistling over us and we were all hoping that they were hitting their intended target.
The following morning the 129th Regiment's Intelligence and Reconnaissance Platoon went to the impact area. It resembled a moonscape. They found one dazed Japanese soldier wandering around aimlessly, and he was brought back to division headquarters for interrogation. By that time he had recovered enough to answer our questions. He verified that the whole 23rd regiment had been caught in the assembly area and had been decimated. He was crying with shame for having left his native Kyushu to fight the Americans and had been unable to fire even one shot.
Through captured documents it was determined that the remaining 13th Infantry Regiment of the 6th Division was down to one battalion strength, the other two battalions were lost on a transport ship sunk going to New Guinea. What remained was a much-weakened enemy force consisting of the independent mixed brigade, one battalion of the 13th and other small units. With the decimation of the 23rd Infantry, for all practical purposes, the battle of Bougainville ended on 23 March 1944. We had complete control of the air and sea around the island and the enemy forces had been denied re-supply of essential men and supplies for months. They were in desperate straits, unable to engage in combat, and barely capable of survival. There were reports of enemy forces clearing patches of the jungle to raise crops of vegetables to survive. At least some genius had the foresight to come prepared with seeds!
1. Hq 37th Inf Div Commendation dated 17 Apr 1944
2. Ltr fr Maj Gen Beightler to Officers and Men of the
37th Inf Div dated 6 Apr 1944