After the seizure of Naha and the area to its east the Sixth Marine
Division prepared to continue its drive to the south by making an
amphibious landing on Oroku. General Shepherd ordered his Division
Reconnaissance Company, a flexible group that worked under G-2 or G-3 as
the situation demanded, to cross the estuary during the night of 1-2
June and reconnoiter possible landing beaches as well as explore the
area inland where the beachhead would be established. Using plastic
boats, the company made its reconnaissance and returned to Naha at 0300,
2 June, to report that the northern part of Oroku Peninsula was occupied
by the enemy but not in great strength.
The plan for the reduction of enemy forces on Oroku was simple and
complete; it left the Japanese no alternatives except to surrender or
die. The Fourth Marines were to make a dawn landing on 4 June and as the
beachhead expanded, the Twenty Ninth Marines were to go in on the left
of the Fourth. With two regiments attacking abreast, the plan called for
the other regiment, the Twenty Second Marines, to throw a cordon-like
line across the base of the peninsula in conjunction with the First
Marine Division as it crossed both forks of the Kokuba river and drove
south. Then with the Twenty Second facing northwest and preventing the
enemy from escaping, the two assault regiments would drive east and
southeast to exterminate the enemy defenders of Oroku.
After the rainy weather of the last week in May and the first few days
in June, the Sixth Marine Division faced a tremendous logistical
problem. Initially the assault regiments would have to be supplied by
amphibious craft over the same route used for the landing. As the attack
moved to the southeast, there was a chance that the Naha Estuary could
be bridged by using little Ona Yama island, which lay in the center of
the estuary, almost equidistant from Naha and Oroku. There were a few of
the enemy on Ono Yama; these would have to be killed before the
engineers could commence their bridging efforts. Simultaneously then,
with the landing of the Fourth Marines on Oroku, the Sixth
Reconnaissance Company was ordered to land on, and secure, Ono Yama. All
through 2-3 June amphibious trucks (DUKWS) and tractors carried supplies
and equipment over impassable roads to the beach at Naha where the
landing was to be launched.
[Illustration: Map 10. Beachhead On Oroku.]
Before dawn, 4 June, the preliminary bombardment commenced on Oroku and
Ono Yama. At 0551, the Fourth Marines landed two battalions without any
great difficulty. Early enemy resistance was light and the troops moved
rapidly inland. At 1000 the Twenty Ninth Marines commenced to load a
battalion to send across to join the Fourth. In the meantime, the
Division Reconnaissance Company had landed on Ono Yama and killed a
handful of Japanese.
Defending Oroku were mixed troops. There were some regular units, some
Okinawa Home Guardsmen, and some were naval and air personnel from units
stationed at Naha Port, and Naha Airfield. The rough character of the
terrain on Oroku, with the exception of the flat ground around the
airfield, lent itself to the defenders. From carefully prepared cave
positions they could use the machine guns, 40 and 20-mm. antiaircraft
guns that had been stripped from the defenses of the airfield. This
enemy group on Oroku, some 5000 strong, had resigned themselves to
making a last ditch stand on the peninsula. Initially, however, the
amphibious landing of the Fourth Marines caught them by surprise. With
the advance of the First Division across the Kokuba toward Itoman, the
enemy apparently decided that Oroku would be attacked from its base, not
its northwest tip, and was originally deployed to fight off any thrust
from the base.
[Illustration: Map 11. Front Lines On Oroku.]
It was indeed unfortunate then, that because of two factors beyond its
control, the Sixth Marine Division was not afforded the opportunity of
really capitalizing on its tactical surprise to the enemy. The rainy
weather through the latter part of May and early June had made Oroku
extremely muddy. What few roads there were that led inland from the
landing beaches were either mined or had sections blown out so that our
tanks could not use them. The rice paddies, fields and hills, ankle to
knee deep with mud, were heavily mined, precluding the possibility of
tank movement and causing the infantry to move with utmost caution. At a
time when speed could have meant rapid gains, the division found itself
forced to let the rifle companies fight as best they could and without
many of their supporting arms. The brief respite gained by the enemy
allowed him to redeploy his forces to resist the attack of the Fourth
and Twenty Ninth Marines.
[Illustration: Map 12. Last Pocket of Resistance on Oroku.]
It wasn’t until 13 June that the enemy forces on Oroku were destroyed.
The Fourth Marines, after landing on 4 June, had seized the first hills
inland and then as the Twenty Ninth came in on the left, the Fourth
secured Naha Airfield and drove to the southeast in an encircling
maneuver. Facing the enemy from the east, the Twenty Second Marines kept
him bottled up and harassed his rear. On the left, driving down the long
ridge that parallels the estuary, the Twenty Ninth moved slowly. In the
extreme broken terrain that characterized Oroku, the enemy resisted
fiercely using all the weapons at his command to prevent the advancing
Marines from crossing the numerous compartments, and denying them the
use of the corridors.
The advance was slow and the action costly. In addition to his automatic
weapons, small arms, grenade discharges and mortars, the enemy had
320-mm. spigot mortars and artillery. Cut off, surrounded, and assaulted
from all sides, the enemy was exacting a final price for the peninsula.
It was not until 12 June that the first real break in his carefully
coordinated defense became apparent. On this day, converging forces of
the Fourth Marines and the Twenty Ninth had the enemy completely
encircled. From his positions, the enemy could look to the northwest and
see the Twenty Ninth; turning to the south, he could see the Fourth
Marines driving in on his flank; behind him was the Twenty Second
Marines, moving in slowly to complete his doom.
During the afternoon of 12 June, some enemy groups came out waving white
surrender flags. Others refused to surrender and pressed grenades to
their stomachs. Still others allowed themselves to be killed while
offering only feeble resistance. In most, the will to live was gone;
they were resigned to their fate. Next day, 861 Japanese were killed and
73 taken prisoner.
Before the capture of Oroku could be called complete, there remained to
be taken the small island of Senaga Shima. After a heavy preliminary
bombardment, the Sixth Division’s Reconnaissance Company, with a company
from the Twenty Ninth Marines attached, landed on the island and quickly
seized it. Only two of the enemy were found and killed but many fine
coastal guns were captured. Now the battle for Oroku was over. The enemy
had resisted bitterly, 1,608 Marines were killed or wounded in the
capture of the peninsula, and thirty of our tanks were lost. During the
ten days of fighting the Sixth Marine Division had killed almost 5,000
Japanese and had captured nearly 200. For its excellent work in landing
on the peninsula, seizing the airdrome and then driving around the
enemy’s position to overwhelm him from the flank, the Fourth Marines was
awarded the Presidential Unit Citation.