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Seizure o f the Kerama Islands
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Seizure o f the Kerama Islands
The first landings in the Ryukyus were on the Kerama Islands, fifteen miles west of Okinawa. The boldly conceived plan to invade these islands six days prior to the landing on Okinawa was designed to secure a seaplane base and a fleet anchorage supporting the main invasion. An additional purpose was to provide artillery support for the Okinawa landing by the seizure of Keise Shima, eleven miles southwest of the Hagushi beaches, on the day preceding the Okinawa assault. The entire operation was under the control of the Western Islands Attack Group. The force selected for the landings in the Keramas was the 77th Division, commanded by Maj. Gen. Andrew D. Bruce; the 42oth Field Artillery Group was chosen for the landing on Keise Shima. 8
Steaming from Leyte, where the 77th Division had been engaged in combat since November 1944, the task force moved toward the objective in two convoys. The as LST's, 14 LSM's, and 4o LCI's, organized into a tractor flotilla with its own screen, left on 20 March. Two days later twenty transports and large cargo vessels followed, screened by two carrier escorts and destroyers. En route, the training begun on Leyte was continued. Operational plans were discussed and the men were thoroughly briefed with the aid of maps, aerial photographs, and terrain models. Booklets on habits, customs, government, and history of the Okinawans were distributed. After an uneventful voyage, broken only by false submarine alarms, the entire task force arrived on 26 March in the vicinity of the Kerama Islands.
Naval and air operations against the Keramas had begun two days earlier. Under the protection of the carriers and battleships of Task Force 58, which was standing off east of Okinawa, mine sweepers began clearing large areas south of the objective area on 24 March. On 25 March Vice Admiral William H. Blandy's Amphibious Support Force arrived, and mine sweeping was intensified. By evening Of 25 March a 7-mile-wide lane had been cleared to Kerama from the south and a slightly larger one from the southwest. Few mines were found. Underwater demolition teams came in on the 25th and found the approaches to the Kerama beaches clear of man-made obstacles, though the reefs were studded with sharp coral heads, many of which lay only a few feet beneath the surface at high tide and were flush with the surface at low tide.9
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While the demolition teams surveyed the approaches, observers from 77th Division assault units studied their objectives. A fringing reef of irregular width surrounds each island. The coasts of the islands are generally steep and irregular. Narrow benches of coral rock lie along the coasts in many places. The beaches are narrow and are usually bulwarked by 4-foot sea walls. The only beaches of any considerable length are at the mouths of steep valleys or within small bays. All but the smallest of the islands are for the most part masses of steep rocky slopes, covered with brush and trees and from about 400 to 800 feet in height. Wherever possible the inhabitants grew sweet potatoes and rice on the terraced slopes of the hills and in small valley flats near the beaches. There are no roads and only a few pack-animal trails. No island in the group is suitable for an airstrip; none can accommodate large masses of troops or extensive base facilities. The military value of the Keramas lies in two anchor?ages, Kerama Kaikyo and Aka Kaikyo, separated from each other by Amuro Islet, in the center of the group, and bounded on the east by Tokashiki and on the west by Aka, Geruma, and Hokaji. These anchorages inclosed 44 berths, from 500 to 1,000 yards long, ranging in depth from 13 to 37 fathoms.10 (See Map No. IV.)
Four battalion landing teams (BLT's) of the 77th Division made the first landings in the Kerama Islands on the morning of 26 March. The sky was clear, visibility good, and the water calm. Escorted by Navy guide boats, waves of amphibian tractors moved from LST's to four central islands of the group?Aka, Geruma, Hokaji, and Zamami. Cruisers, destroyers, and smaller naval craft swept the beaches with 5-inch shells, rockets, and mortar shells. Carrier planes strafed suspected areas and guarded against interference by enemy sub?marines and aircraft. Amphibian tanks led the amtracks to the beaches.11
The first unit ashore was the 3d BLT of the 305th Regimental Combat Team (RCT). At 0804 12 the 3d BLT hit the soutfiern beaches of Aka, an island of irregular shape, measuring 3,400 by 3,000 yards at its extreme dimensions and rising in a series of ridges to two peaks, one 539 feet and the other 635 feet high. Aka, "Happy Corner Island," lies near the center of the group. The 200 boat operators and Korean laborers on Aka put sporadic mortar and machine-gun fire on the Americans, without inflicting damage, and then re-
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TERRAIN IN THE KERAMA RETTO was rugged. In particular the coastal terrain was precipitous, appearing formidable to the 2d BLT, 306 Infantry, 77th Division, as it approached Hokaji Island on 26 March. Below is an aerial view of Tokashiki Island.
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treated into the steep central area as the invaders rapidly overran the beaches and the town of Aka.
The next island invaded-and the first to be secured-was Geruma, a circular island five-eighths of a mile in diameter, lying south of Aka. The 1st Battalion Landing Team of the 306th Regimental Combat Team landed on the narrow beach at 0825, meeting no opposition except for long-range sniper fire. Within three hours it wiped out a score of defenders and secured the island. Before the engagement was over, DUKW's began unloading 105-mm. howitzers of the 304th and 305th Field Artillery Battalions for use in operations scheduled for the next day.
The easiest conquest of the day was that of Hokaji, an island one mile by Boo yards, lying a few hundred yards south of Geruma and linked to it by an encircling reef that follows the contours of the two land masses. The 2d BLT of the 306th landed on Hokaji at 0921 and secured it without resistance.
At 0900 on 26 March the 1st BLT of the 305th invaded Zamami, initially meeting little resistance. A two-legged, humpbacked island, approximately 5,500 yards long east-west and 400 yards at its narrowest point, Zamami is formed, except for a few low flat areas along the southern coast, by a group of wooded hills which rise about 450 feet. Amtracks carried the troops ashore in a deep bay that cuts into the southern coast. A sea wall fifteen feet from the water's edge held up the amtracks and forced the men to continue by foot. The assault elements received sporadic mortar and sniper fire until they reached the town of Zamami, just to the rear of the beach. Then a group of Japanese estimated to be of com?pany strength, together with about 3oo Korean laborers, fled north from the town to the hills.
It became apparent to General Bruce by late morning of 26 March that the rapid progress of the landing teams would permit the seizure on the first day of an additional island. Accordingly the 2d BLT of the 307th, a reserve unit, was directed to seize Yakabi, northwesternmost islet of the Keramas, which was nearly oval in shape and a little more than a mile long. At IM 1 the battalion landed on Yakabi and, meeting only slight opposition, quickly overran it.13
On both Aka and Zamami the invading forces met stiffer resistance as they pressed up the steep slopes into the interior of the islands. On Aka a group of Japanese of platoon strength was routed by naval gunfire. During the afternoon the troops killed fifty-eight Japanese in a series of brief skirmishes
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on the eastern heights of the island. Though the enemy fought from caves and pillboxes with small arms, he had no effective defense. By 1700 of 26 March two-thirds of Aka was secured; 300 Japanese troops and 400 civilians were still at large on the island.
On Zamami advance elements of the 1st BLT of the 305th pushed up into the high ground during the afternoon without closing with the enemy. From midnight until dawn of the next day, however, groups of Japanese armed with rifles, pistols, and sabers tried to break into the American peri?meters near the beach. Company C bore the brunt of the attack, repulsing nine local thrusts supported by automatic weapons and mortars. One American machine gun changed hands several times. In a series of night fire fights that at times developed into savage hand-to-hand combat, the 1st Battalion killed more than zoo of the enemy at a cost of 7 Americans killed and 12 wounded.14
On 27 March the Americans took without opposition Amuro, an islet between the two anchorages and Kuba, the southwesternmost of the Keramas. Fitful action was still in process on Aka and Zamami on the morning of 27 March. On Aka the 3d BLT of the 305th isolated seventy-five Japanese who were dug in on a ridge and its reverse slope and were fully supported by mortars and automatic weapons. After a period of aerial strafing, bombing, rocketing, and mortar fire, the Americans drove the enemy from their position into the brush. On Zamami patrols of company size reconnoitered the island and eliminated scattered groups of the enemy. One organized position was located but could not be assaulted until the following day, when amtracks blasted frontally the caves where the last Japanese to be found were dug in.
After a preparation by artillery firing from Geruma, the 1st BLT of the 306th landed on the west coast of Tokashiki at 0911 of 27 March, and a few minutes later the 2d BLT landed to the south of the 1st. Tokashiki was the largest island in the group, six miles long from north to south and aver?aging about one mile in width. Closest of the islands to Okinawa, it formed the eastern barrier of the Kerama anchorages. Its coasts rise for the most part as cliffs or steep slopes cut by narrow ravines, the hill masses reaching heights of more than 650 feet in the center of the island and at the northern and
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southern ends. At the backs of two sheltered bays near the center of the west coast there are two settlements, Tokashiki and Aware; the sandy beaches near these bays were selected by the invaders for the landings.
Operations on Tokashiki followed the pattern of those on the other major islands of the Keramas. Resistance at first was negligible, the Americans being hindered more by the rugged terrain than by the scattered sniper fire. The two battalions abreast drove north over narrow trails. The 3d BLT of the 3o6th, initially in reserve, was landed with the mission of clearing the southern portion of the island. By nightfall the 1st and 2d Battalions were set for the next day's attack on the town of Tokashiki on the east coast; 3d Battalion patrols had reached the southern tip of the island.
On the following day, 28 March, the two battalions of the 306th renewed their drive to the north. After a 500-round artillery preparation the troops occupied Tokashiki, which had previously been leveled by air and surface bombardment. The area near the bay was overrun without opposition. The advance continued to the north, meeting only scattered resistance. On 29 March, after the three battalions had sent patrols throughout the island, Tokashiki was declared secured.
By the evening of 29 March all islands in the Kerama Retto were in American hands. In all, combat elements of the 77th had made fifteen separate landings, involving five ship-to-shore movements by LVT's, two ship-to-shore movements by DUKW's, three ship-to-shore movements by LCVP's with subsequent transfer to LVT's, and five shore-to-shore movements by LVT's. Despite the complexity of the maneuvers, the veterans of Guam and Leyte operated with little confusion. Casualties were low. From 26 to 31 March the 77th killed 530 of the enemy and took12Iprisoners, at a cost of 3I Americans killed and 81 wounded.15
The operations on Aka and Tokashiki had interesting consequences. Al?though 77th Division patrols scoured the islands, hundreds of Japanese soldiers and civilians managed to evade discovery in caves, ravines, and brush through?out the hilly central parts of the islands. After the Okinawa operation, representa?tives from Tenth Army tried unsuccessfully to induce the Japanese commander on Aka to surrender. The Japanese soldiers and sailors were not as stubborn, and most of them escaped from the island and surrendered. On Tokashiki teams of Nisei and Japanese officer prisoners negotiated with the Japanese commander, who refused to surrender his garrison of 300 officers and men. He offered, how-
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ever, to allow Americans to swim on Tokashiki beaches provided they kept away from the Japanese camp in the hills. Only after many months, when he was given a copy of the Imperial rescript announcing the end of hostilities, did the Japanese commander surrender, claiming that he could have held out for ten more years.16
The capture of the Kerama Islands was followed by the landings on Keise Shima. Lying about eleven miles southwest of the Hagushi beaches and about eight miles west of Naha, the group of four tiny coral islets that make up Keise had an importance in the attack on Okinawa far out of proportion to its size and topography. From Keise 155-mm. guns could command most of southern Oki?nawa. Employing tactics used with great success on Kwajalein, Tenth Army ordered XXIV Corps artillery to emplace two battalions of 155-mm. guns on Keise to support the attack.
On 26 March the Fleet Marine Force Amphibious Reconnaissance Battalion, attached to the 77th Division, scouted Keise without encountering enemy troops or civilians. On the morning of 31 March a convoy of LST's and LSM's bearing the 420th Field Artillery Group and attachments arrived off the islets. Over floating caisson docks set up by Seabees the heavy guns and other equipment were unloaded. Twenty-four 155-mm. guns were emplaced on the low, sandy islets, and a cub strip and a bivouac area were established. By dawn of L Day the batteries were ready to execute their mission of firing counterbattery, interdiction, and harassing fires deep into enemy territory.
The guns were set up in full view of the Japanese occupying high ground on Okinawa. General Ushijima ordered a "surprise shelling" of Keise to begin at midnight of 31 March, after which army and navy commands were to dispatch "raiding infiltration units" to Keise, "thereby wiping out the enemy advanced strong point in one blow." 17 For an hour after midnight, Japanese 250-mm. shells exploded on the islets. There were no casualties or damage. The infiltration party never appeared. This attempt to destroy the artillery on Keise was only the first of several, the enemy being keenly aware of the threat offered by the artillery in this flanking position. 18
The assault on Kerama and Keise had come as a surprise to the Japanese commanders on Okinawa Gunto. The enemy commanders on Okinawa had
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expected that the Americans would land first on the Hagushi beaches and that their ships would deploy just east of the Kerama Islands.19
Since the enemy considered the Keramas as bases for special attack units rather than as defensive positions, there were few prepared defenses on the beaches or inland when the Americans appeared. At one time 2,335 Japanese troops occupied the islands, engaged in installing and operating facilities for the Sea Raiding units. When, in late 1944 and early 1945, the need for combat troops on Okinawa became acute, most of these troops were moved to the larger island. There remained on the Kerama group only about 300 boat operators of the Sea Raiding Squadrons, approximately Goo Korean laborers, ana about 100 base troops. The garrison was well supplied not only with the suicide boats and depth charges but also with machine guns, mortars, light arms, and ammunition.20
In Kerama Retto, "Island Chain between Happiness and Good," the Japanese tradition of self-destruction emerged horribly in the last acts of soldiers and civilians trapped in the hills. Camping for the night of 28 March a mile from the north tip of Tokashiki, troops of the 306th heard explosions and screams of pain in the distance. In the morning they found a small valley littered with more than i5o dead and dying Japanese, most of them civilians. Fathers had systematically throttled each member of their families and then disemboweled themselves with knives or hand grenades. Under one blanket lay a father, two small children, a grandfather, and a grandmother, all strangled by cloth ropes. Soldiers and medics did what they could. The natives, who had been told that the invading "barbarians" would kill and rape, watched with amazement as the Americans provided food and medical care; an old man who had killed his daughter wept in bitter remorse.21
Only a minority of the Japanese, however, were suicides. Most civilians straggled into American positions, worn and dirty. In all, the 77th took 1,195 civilian and 121 military prisoners. One group of 26 Koreans gave up on Zamami under a white flag. On Aka one Japanese lieutenant surrendered voluntarily because, he said, it would be "meaningless" for him to commit suicide.22 A Japanese
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LANDINGS IN THE KERAMAS, made by the 77th Division, met little opposition. Zamani Island (above) was taken by the 1st BLT, 305th Infantry, some soldiers of which are shown just before the started inland. Amtracks were unable to negotiate the seawall and were left at the beach. Below is a scene on a beach at Tokashiki, captured by the 1st BLT, 306th, on 27 March. Soldier (right) seems puzzled by the absence of opposition.
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major captured by a patrol on Zamami late in May assisted in efforts to induce Japanese remaining in the islands to surrender.
More than 350 suicide boats were captured and destroyed by the 77th in the Kerama Islands. They were well dispersed throughout the islands, many of them in camouflaged hideouts. These plywood boats were 18 feet long and 5 feet wide. Powered by 6-cylinder Chevrolet automobile engines of about 85 horsepower, they were capable of making up to 20 knots. Two depth charges weighing 264 pounds each were carried on a rack behind the pilot and were rolled off the stern of the boat when released. According to captured instructions, three boats would attack a ship simultaneously, each seeking a vital spot to release its charge. Strictly speaking, manning the boats was not suicidal in the same sense as piloting the Kamikaze planes or the "Baka" bombs. Delay time for the depth-charge igniters was five seconds. According to a Japanese officer, it was considered pos?sible to drop the depth charges against a ship and escape, but the fragility of the boats made survival highly unlikely. As a result, the pilots were promoted two grades upon assignment and received preferential treatment. After com?pletion of their missions they were to receive promotion to second lieutenant; obviously, most such promotions would be posthumous.
From hideouts in the small islands, the "Q-boats" with their charges were to speed to the American anchorages. "The objective of the attack," General Ushijima ordered, "will be transports, loaded with essential supplies and material and personnel . . . . The attack will be carried out by concentrating maximum strength immediately upon the enemy's landing." 23 The Japanese had carefully mapped out possible assembly areas of American transports and had prepared appropriate routes of approach to each area, especially those around Keise.24 The initial thrust into the Keramas completely frustrated the enemy's plan. In the opinion of General Bruce, the destruction of the suicide boat base alone was well worth the cost of reducing the Kerama Islands.25
In a campaign that found the Japanese prepared for the major moves of the invading forces, the initial seizure of their "Western Islands" not only caught them off guard but frustrated their plan of "blasting to pieces" the American transports with a "whirlwind" attack by suicide boats.26 The Americans gained
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"SUICIDE BOATS" wrecked by their crews were found by the 77th Division as it mopped up in the Keramas. They looked like small speedboats but were poorly constructed and quite slow, These two craft (below) were captured in their cave shelters by American troops on Okinawa. Note booby trap warnings and crude depth charge racks at stern.
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SOFTENING UP THE TARGET was the task of the allied fleet. It stood off Okinawa to place accurate fire on known Japanese installations and to support underwater demolitions teams clearing the beaches. At the same time the fleet's air arm conducted aerial bombardment. This low-level bombing attack on L minus (below) hit enemy shipping in the mouth of the Bishi River.
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even more than the Japanese lost. In American hands, this sheltered anchorage became a miniature naval base from which seaplanes operated and surface ships were refueled, remunitioned, and repaired.
