96th Infantry Division Troops Flush out Japanese Troops on Okinawa using M-15 White Phosphorus Hand Grenades

Document Source: Operations of the 382nd Infantry Regiment, 96th Infantry Division, in the Penetration of the Japanese Naha-Shuri-Yonabaru Line, on Okinawa, May 10, 1945, – May 31, 1945. Ryukyus Campaign. Experience of Maj Joseph F. Vering, Company Commander.


This archive covers the operations of the 382nd Infantry, 96th Infantry Division, in the penetration of the Japanese Naha-Shuri-Yonabaru Line, from May 10 to May 31, 1945. A brief description of events leading to the action is included to familiarize the reader with the situation and conditions as they existed at the time of these operations. During the year 1944 and the early part of 1945, a series of brilliant land and sea victories brought our fast-moving Armed Forces well on their way to driving the Japanese back into the bailiwick from which they had launched their infamous attack on the peace-loving peoples of the Pacific. The time was ripe for preparing the attack against the very heart of this treacherous enemy – the Japanese Homeland. The Joint Chiefs of Staff, therefore, directed the Commander in Chief, Pacific Ocean Area to occupy one or more positions in the Ryukus Islands. The reasons for the occupation of these islands as stated in the directive were as follows: (1) To establish bases from which to: (a). attack the main Islands of Japan and their sea approaches with Naval and Air Forces; (b). support further operations in the region bordering on the East China Sea; (c). sever Japanese sea and air communications between the Empire and the Netherlands East Indies. (2). To establish secure sea and air communications through the East China Sea to the Coast of China and the Yangtze Valley. (3). To maintain unremitting military pressure against Japan.

Pacific Theater Orientation Map - General

US 10-ASon of a Confederate General and the highest ranking US officer killed by enemy fire in the Second World War, USMC Maj Gen Simon Bolivar Buckner Jr on Okinawa, Summer, 1945In the accomplishment of the directive as outlined, the US Tenth Army, commanded by Gen Simon B. Buckner, was assigned the mission of assisting in the capture, occupation, defense, and development of the Okinawa Island, and the establishment of control of the sea and air in the Ryukyus Area, with the eventual aim of extending control over the entire Ryukyus by capturing, defending, and developing additional positions.

III Amphibious CorpsXXIV CorpsThe Tenth Army operational plan included the Okinawa landing on L-Day (April 1, 1945) with two Corps abreast. The III Amphibious Corps was to land on the left, drive rapidly inland, turn north, and block off that portion of the Island. Simultaneously, the XXIV Army Corps would land on the right, drive rapidly inland cutting the Island in two, then turn south to capture that portion of the Island.

The landings were almost without opposition. The Japanese failed to man their elaborately prepared positions covering the landing beaches. The coral reefs surrounding the landing beaches apparently led the Japanese to believe that no major assault forces could be landed across them and to commit that often-repeated error in the history of defeated armies – too much faith in an obstacle. This false sense of security cost the Japanese his golden opportunity to inflict heavy losses on the American forces while crossing the exceedingly vulnerable beaches. By L+4, the XXIV Corps had advanced to or beyond a line that had been designated in the plan as the L plus 10 Line. The III Amphibious Corps in the first few days accomplished their mission and secured the entire northern part of the Island with little opposition.

American ships landing troops and supplies on a beach on Okinawa, Japan, 13 April 1945

Area Map - Okinawa April 1945


US 7-IDThe splendid execution of the initial phase of this operation is unquestionable without parallel in the history of amphibious warfare. The almost unbelievable success of the first few days led to a rumor that the Japanese had been caught with their pants down and that the famed 32nd Army had moved from Okinawa to Formosa, expecting American forces to land there. This was one rumor that needed no squelching. The 27-IDrapidly mounting resistance in the XXIV Corps Sector soon had everyone convinced that capturing the southern portion of the Island would be a hard and costly struggle. By L+10, there were three divisions on the line in the XXIV Corps Sector, the 7th Infantry Division, the 27th Infantry Division, and the 96th Infantry Division. In the center of the line, the 96th Infantry Division, of which the 382nd Infantry Regiment was a 96-IDpart, advanced against every mounting resistance until they met the first heavily defended and stubbornly held Japanese positions, Tombstone Ridge and Kakazu Ridge. Here, the advance ground to a halt, and not until April 24, after the most bitter kind of hand-to-hand fighting, were these positions taken.

The Japanese commander may have erred by abandoning his beach defenses, but his decision to withdraw all his troops to the south, where he systematically organized key terrain with maximum troops and weapons, was beginning to pay dividends. The 96th Infantry Division lost 2004 men during this action; however, thanks to the tremendous amount of firepower available to the American infantryman, he was causing enemy casualties in the ratio of two for each American casualty. During the same action, the division killed 4663 and captured 6 Japanese. Another week of bitter fighting reduced the combat strength of all regiments in the 96th Infantry Division to about 52%. As always when ground combat casualties are high, the regiments were almost depleted of front-line riflemen. Combat efficiency had reached a low ebb; those remaining were badly in need of rest, clean clothing, and a bath. Consequently, the 96th Infantry Division was relieved from front-line duty on April 30.

Okinawa - Japanese Forces


Moving out of the lines with the 96-ID, the 382-IR was placed in a rest area near Koza. To the soldier who had seen newsreels of our European rest areas with soft beds, swimming pools, good-looking girls, and dances, the rest area was hardly the name for Koza. Unfortunately, Japanese artillery firing at a nearby airstrip continually missed just far enough to land in the center of the rest area and was a constant source of harassment to the resting troops. Despite this, it was a relief from the front lines. Shelter tents were pitched over slit trenches, kitchens were set up, and it was only a short walk to a bath unit. Every man was given clean clothing and all equipment was put in excellent condition.

On May 1, 1100 replacements were received by 382-IR. To the combat veteran, they were a sorry-looking group – 19 and 20-year-old boys with only a few weeks of basic training, completely without organization and leaders. These men were promptly assigned to companies, and given as much training as possible, with emphasis on small unit tactics, patrolling, and the use of demolitions materials. This training proved to be particularly effective. Realism was provided by the occasional Japanese soldier who practice patrols encountered, and the destruction of the caves in which these Japanese took refuge. The rest period was a short one. Just one week after receiving the replacements, the 96-ID was ordered to relieve the 7-ID in its zone of action. On May 8, the 382-IR was placed under the operational control of the Commanding General 7-ID and moved to a forward assembly area immediately south of Tanabaru. The following day, the regiment relieved the 17th Infantry Regiment in its zone of action south of Kochi.

This zone of action was nothing else than a range of succeeding hills to the south, higher, and dominated those to the north. The Japanese commander had chosen his terrain to defend all too well. This was ideal at about 6000 yards deep, making maximum use of all the hill masses in the area. By virtue of their observation and geographical arrangement, all were able to support by fire anyone or group that was attacked. Each hill was prepared for defense by a complete network of tunnels and caves. These were, in most cases, large enough to provide living and storage space for the occupying troops. Mole-like digging turned the hills into fortresses providing cover, concealment, and completely safe routes through which troops could move to mass their fires on any attack from any direction. Hundreds of firing positions for all types of weapons were provided by openings leading into the tunnels on several levels in all directions. Every firing position had its own field of fire and was mutually supporting with many others.

The valleys between the hills afforded ideal areas for obtaining maximum range and interlocking bands of fire. Primary firing positions were protected by well-dug foxholes around the openings and communication trenches which ran both laterally and from front to rear. As near as can be determined, the Japanese plan for occupation and use of these positions was to have a few men stationed in foxholes outside the caves who were to give a warning when our supporting fires had lifted or our assault began. Then all firing positions were to be occupied with approximately equal strength on the forward slope, the crest, and the reverse slope. Once the defenders were dislodged from the forward and crest positions, the most tenacious part of the defense would begin.

Japanese Defenses are perfectly integrated into the nature of the area - Okinawa 1945

(Note Doc Snafu: It looks like pages 12 & 13 are missing in this archive)

The Japanese made repeated attempts to retake their lost positions. Almost constant mortar and artillery fire were placed on the 1st Battalion. At about 2200 hours, the Japanese launched a strong counter-attack, which was not the typical crazy banzai raid, but well-organized and desperate. The battalion’s outpost was destroyed and the attack developed into a hand-to-hand grenade and bayonet fight which lasted until 0730 hours the following morning. When the fighting finally ceased, 122 enemies dead were counted on the position. The 1st Battalion losses: 14 killed and 62 wounded. It had been a successful but costly day. The regiment had accomplished its mission by gaining a splendid position from which to participate in the Tenth Army attack.

Here a word should be said in praise of the fine Naval cooperation. By firing recently developed illuminating shells, they kept enough visibility over the area so that our troops could tell friend from foe. The outcome of this counter-attack and the many which were to follow may well have been decided by this support. The regiment’s first objective in the Tenth Army attack, the Dick Hill mass, had four distinct peak-like ridges, Dick Left, Dick Eight, Dick Able and Dick Baker. Despite the all-night counter-attack, the regiment jumped off as scheduled. The Japanese continued to stubbornly defend the reverse slope of Zebra Hill. After placing all the available artillery and mortar fire on these positions, the 1st Battalion attempted to cross the rest but was immediately repulsed. At about noon, Charlie Co, with a platoon of tanks attacked, were able to fight their way around to a nose on the right flank which provided positions from which they could lay a base of the fire, pinning the Japanese in their holes while the other two companies launched a coordinated attack and quickly closed on the Japanese positions.

US Marines clearing a traditional burial tomb during the Battle of Okinawa, May 1945

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