All the information given in this section was taken
from translations of Japanese documents of various
types; most of them were written within the past few
months. They deal almost exclusively with warfare in
jungle areas. In some instances, the information has
been rearranged or paraphrased in order to make it
more logical and readable.
2. APPROACH TACTICS
After having passed through the enemy lines, and while making
a reverse turn in the jungle (attack from the rear), absolute
secrecy is still essential to success in attacking the enemy. Each
unit will bear this in mind, and will see that each individual
soldier clearly understands our plan of attack.
Special precaution must be taken in regard to the following points:
a. Cooking operations must be carefully concealed, both day
and night. Cooking must cease at least 1 hour before daybreak, and
the fire must be extinguished completely. In going to a
river for water or bathing, it is necessary to select the naturally
concealed places, or to camouflage a place from enemy air observation.
b. During the approach in thick forest, liaison is made chiefly
by telephone and messenger. Prohibit the use of radio. These
methods are to be changed only after the attack is started.
c. If the approach is along a road, the road should be wide; if
not, remove the weeds near it. However, do not let the
changes become visible from the air. Units making a round
trip should strictly enforce rules for passing on the left flank, and
should prevent delay in the advance.
d. Do not make the forest thin by such action as would damage
the large trees near roads and bivouac areas.
e. Progress through clearings and open places in the jungle, must
be made swiftly and in an orderly manner. Again, when
enemy planes are overhead, the unit is required to stop
temporarily, even in a forest, if there is any possibility
of being observed.
f. It is necessary to take precautions against talking out
loud or shouting, even in the forest, because of native spies, enemy
sound detectors, and enemy scouts. This is especially the
case when close to the enemy position. Again, if the natives are
being sighted, it is necessary to kill them immediately.
g. During the movement of each unit, it is necessary to organize
an observation party to carry out strict supervision and observation
of this movement and to take various other precautions.
h. The approach-march speed of units in the forest must be the
same as that of heavy fire weapons. Include in original plans
the sending ahead of time of a supply of ammunition
and a 12-day supply of provisions.
i. It is necessary for each unit to secure close control in
thick forest, using rest periods to reassemble the main force. Particularly
because of soldiers being delayed and falling out of
rank, it is necessary for leaders to keep strict supervision.
3. DEPLOYMENT TACTICS
a. The commanders (accompanying an advancing construction
unit), together with engineer personnel, will go to the jump-off
position being prepared for the division, and will select and
mark the sectors to be occupied by the various units. Especially
try to scatter each unit involved in the initial fighting, selecting
good camouflaged positions. You must take all precautions
against enemy discovery. In case you are discovered and receive
shells from the enemy, you must be prepared to take any measures
b. Then each front-line commander will reconnoiter his terrain
in preparation for advancing, will indicate the nature of
routes to be taken, and will select the next stopping place
c. Movement of the main division force to the jump-off position
must be made one night before the day of attack. It is
very important to carry out these instructions without
confusion, shortening the day of readiness in front of the
enemy as much as possible.
d. Each infantry regiment in the division jump-off position (generally
about 3 2/3 miles inside the forest) will make a
deployment. Then each battalion in the first line will select a battalion
deployment position, temporarily on a line generally
about 1 1/2 miles inside the forest. Deploy after
advancing to this line on the route which is already
constructed, and again prepare for attack.
e. Each company on the first line will naturally have the
approach route open up to the time the battalion advances into
the jump-off position, and will approach to approximately 1 1/2 miles
from the edge of the forest (same as the battalion deployment line) and
make a deployment. Then the preparation of
the attack will be made. Afterwards, a leader is required to
make a reconnaissance before the attack. Hereafter, at dusk, you
will advance to the line at the edge of the forest; if necessary, crawl
through the jungle zone, and immediately rush on
to the enemy position after giving the signal.
As it is best for each flank unit to make a rush at the same
time, the time should be regulated. Therefore, consider the
distance of the forest line and plan for a simultaneous rush.
f. When approaching the enemy, the possibility of encountering
enemy patrol and security units must be taken into consideration.
It is necessary to annihilate them, as far as possible,
and not make any errors. It is necessary to make plans for
immediate annihilation of lookout facilities and microphones of
enemy artillery organizations when they are discovered.
g. During an approach to an attack, each commanding officer
must take the responsibility for maintaining the direction of
advance and make the line of development parallel to the enemy
line. Even though there are times when enemy fire is received, it
is necessary to control the subordinates and not let the unit
4. COMBAT TACTICS
a. Control of units is the key to successful attack in a dense
forest (jungle). When each flank unit makes a rush at the same
time, as one group, no matter what the position may be, it can
b. Flanks of enemy positions can easily be discovered by light
tracer bullets. Therefore, every effort should be made to rush
from the flanks. It is also very important to assault by immediately
chasing the retreating enemy without stopping. When the enemy
has observed our assault, he will retreat and concentrate
his fire on the point just evacuated. At this time give a part
of the unit the previous duty (the assault), and make a suicide
attack into the enemy positions, especially at the antitank
gun position. Attack the remaining enemy with mopping-up action. It
is very important to make a complete annihilation by dawn.
c. The enemy is very fearful of our assault, and each unit has
a tendency to gather into groups. Against such an enemy, hand
grenades are very effective.
d. The units rushing the area around an airdrome must try to
avoid setting equipment on fire or spilling gasoline. Shoot at the
rubber tires and not at the engine of a plane.
e. When advancing to an attack through a dense forest, take
precautions on open ground as there may be cases when there is
a zone of concentrated enemy fire.
f. When a large number of enemy prisoners are taken during
the progress of combat and are looked after by small groups of
guards, it is best to take away their weapons and remove their shoes.
g. Take measures to prevent attacks on the left, right, front, and
rear of the friendly force. Moreover, carry out the signs of the
commanding officer and select each ranking officer to carry out
controlled leadership, taking precautions to maintain the thrust
to the end.
5. OBSERVATIONS OF JAP OFFICERS
This paragraph consists of tactical opinions given by
all officers of a Japanese battalion--after they had experienced
considerable combat against United Nations forces
in Southwest Pacific islands. A preface to the
document stated, "Each unit creates necessary devices, based
on these opinions, after considering the enemy combat methods."
a. Marching Through Jungle
(1) Leave some distance between the engineer unit and the units
that follow. Moreover, have liaison men advance at least 200
to 525 yards ahead.
(2) The leader at the head must always allow for deviation of compasses.
(3) It is advisable to assemble each unit when resting, as it is customary to
march over the road in single column.
(4) Because jungle units carry lights, the commanding officer must advance
his unit by leaps and bounds from one defiladed area to another.
(5) The engineer unit must regularly report to the commanding officer in the
rear regarding the status of preparations and terrain features at the front.
(6) Camouflage of each individual and each gun must be thorough. Moreover, when
crossing a grassy plain, camouflage by using the grass.
(7) If enemy planes are overhead while you are in a grassy area, lie
prone in the tall grass and hide the body by placing grass over it with both hands.
(8) Generally, infantry assistance is necessary for heavy weapons
units. The minimum is one platoon for a machine gun and one platoon
for an infantry battalion gun.
(9) The rate of march for a unit during a day should be about 4 to 6 miles.
(10) It is advantageous to select a route where water supply is possible.
(11) Although it is best to relieve the engineer unit each day, the leading
officer in the front should continue his duty.
(12) When bivouacking in the jungle, it is best to begin sleep at 3 o'clock. Cooking
must be performed at the last resting place before reaching the bivouac area, which
should be, completed before the units arrive. This is safe and also tends to
hide the bivouac area, making it difficult of discovery by enemy planes (at
least two men from each squad should be sent forward to prepare the area).
(13) Be at ease while cooking. Use "marsh reed" and bamboo to make
fires. It is necessary to cook in several places, not just one. Moreover, it
is important to be ready to put out fires immediately in case enemy planes
(14) During this military operation, there was never a time when we were
discovered by enemy planes while in the jungle. It is significant that
enemy prisoners never move, even at night, when planes fly over.
(15) When in flat country, the commander should be in the center of his
unit. When on a hill, he should be at the highest point.
b. Night Attacks
(1) Never be overconfident with aerial photographs, especially
those taken before enemy occupation, because he will make
changes. Pictures of areas directly to our front are extremely
necessary for the execution of the attack, and they should be distributed
at least down to the first-line assault company. This is
especially necessary when maps are not available.
(2) It is important to have sufficient time to move into a jump-off
position for an attack. Going long distances to an assault
without eating on the way will only tire personnel.
(3) It is advantageous to use as leaders the fatigue personnel
of the navy and the present area guides.
(4) It is very important to consider the effective zone of enemy
artillery and mortar fire. If units are rushed into the jump-off
position when the enemy artillery is not neutralized, useless damage
may result. Only the cadre should advance, and it is ideal to
set the time for departure of attack about 10 minutes beforehand.
(5) If artillery fire is not received, it is best to assault without
hesitation because heavy losses may result if time is spent in idle complaints.
(6) Most of the fire from enemy positions consists of light
tracer bullets. Therefore, the enemy line becomes clear and distinct.
It is impossible to attack the front or to assault with a/large
force. It is important to send one or two squads around to make
an assault on the flank. To make a simultaneous attack, wait for an
opportune time and then yell. The noise is very successful in
demoralizing the foe.
(7) If a rush is made into the enemy firing line, concentrated
enemy artillery fire will always be received; therefore, it is best
to rush only when close to the enemy. After penetrating the
firing line, engage the scattered enemy soldiers again. Therefore, it
is necessary to leave one unit (one squad) behind to carry out
the mopping-up work.
(8) It is very important for the cadre and men to immediately
cut communication and liaison lines within a position.
(9) There is an inclination for the subordinates to scatter by
themselves when concentrated enemy fire is received, and it is
necessary to mark the position of the company commander and
control the men (subordinates) for a wholehearted assault. Moreover, give
the men a positive reason for, and an outline of, the
company's conduct of battle. It is also necessary to place in each
group someone able to use a compass.
(10) The majority of losses are caused by artillery and by pursuing
gun fire. Therefore, when they cannot be neutralized, it is
necessary for a plan of suicide occupation. In artillery
positions there are many automatic weapons with formidable
protection, and other strong establishments.
(11) There are many dead spaces within the enemy position. Give
the first-line unit adequate front to investigate the dead
space and use this to expand the success of battle from the rear
and to the flanks. It is also advantageous to assault. In general
we do not investigate dead spaces skillfully.
(12) Complete silence is necessary, since concentrated fire can
be received even within a position.
(13) Do not use radios, because fire will be concentrated in their vicinity.
(14) The liaison between regimental and battalion headquarters
must be carried out by wire, orderly, and other means.
(15) The control of soldiers' voices and markings for commanding
officers is inadequate. Therefore, it is necessary for
thought to be given to these matters the day before the attack begins.
(16) To carry on the battle after daybreak, the heavy guns
must advance during the night--advancing over long distances
after daybreak is impossible. A section of the heavy gun cadre
must advance behind the first line, reconnoitering the route of
advance, and have the unit in the immediate rear pay strict attention.
(17) The enemy usually fires on our jump-off position all night
long. It is necessary to advance to the front of the rear unit
during a lull in the firing.
6. NOTES BY A MARINE COMMANDER
The information in this paragraph was taken from a Japanese
bulletin, prepared by a Marine (Naval Landing Party) commander
and designed especially for unit commanders of Marine forces. The
bulletin apparently was written before the Japanese met
severe opposition in the Southwest Pacific Islands.
a. Handling Personnel
Would you throw away the lives of your men, who have been placed in
your keeping by the Emperor, by recklessly sending them on a frontal
charge in the face of the enemy fire and ignoring your own shortcomings
in leadership and strategy? As a commander, bear this well in mind.
In a word, your object must be to attain the greatest results
with the smallest sacrifice. If you order your men to advance,
they will obey you in any circumstances and at all times. But
remember that before doing this, you are to take the minutest
precautions. Do not forget to explain to your men, as carefully
as if they were little children, how and in what direction to advance,
the places to watch, and what to do when shelled or attacked
by hand grenades.
For example, how many men would have come through unscathed
if they had been ordered to "lie down until your head is on
the ground." This may sound like a graceless criticism of men
who have given their lives, but I believe many men have become
casualties through their own carelessness and want of caution.
It is true that we have dedicated our lives to the nation and will
not begrudge them at any time, but we want to accomplish something
by our death--not die uselessly. We want to die gloriously. We
hope for a death worthy of a Samurai... and we owe it to the men
under our command to enable them to do likewise. If you do
this, as the commanders of a unit, your mind will have
a measure of peace.
In maneuvers, we have always had it emphasized that we must
get a grasp of actual conditions. During the battle of east
Hwatelo (in China) a certain unit commander boasted that he
had decided to make a charge, and thereby greatly embarrassed
his company commander. I believe this was a case of blind
decision. We had been ordered by the battalion commander to
strengthen our position and defend it to the death--this meant, if
your arms are broken, kick the enemy; if your legs are injured, bite
him; if your teeth break, glare him to death. This spirit is
expressed in the words "defense to the death." The time to
launch a charge is when the enemy has reached the limit of
exhaustion, as laid down in the manual. In defense, we believe
that if you can hang on to a position with one light machine gun, one
platoon can successfully crush the enemy.
The unit commander must not give up hope or make pessimistic
statements. In a battle, always remember the "4 to 6 ratio"--if 4 of
our men are knocked out, consider that we have got 6 of the
enemy. Whatever may be our own losses, strive to keep up morale. The
more violent the fighting, the calmer and firmer must be the
commander's bearing, orders, and words of command. It is also
important, in the interest of morale, not to let the personnel of the
unit know the number of killed and wounded, or their names. Heavy
enemy shelling also affects morale, and sometimes troops
will not fight as they should. The effect is still more marked
when there are casualties.
Some young soldiers think it heroic to expose themselves to the
enemy. Take care of this, particularly in a battle of positions.
When fighting is protracted, there is a tendency to get accustomed
to the enemy, and relax vigilance against enemy fire and
hidden enemies. We have been sniped time and again. Pay particular
attention to this.
b. Pointers on Close Combat
Too long a halt in the same area will result in drawing concentrated
fire from the enemy, and is inadvisable. The proportion
of hits from bullets is smaller while you are moving than
when you are stationary. In a charge, if you meet concentrated
fire from the enemy at close quarters and lie down and stay
glued to the same spot, you cannot advance. Also, the longer
you halt, the more your will to advance is blunted, and the
greater your casualties. Therefore, charges must be made with
determination and daring. A daring and determined attack is
the key to victory.
In a charge, the platoon commander must be at the head, as
indicated in the manual. The charge is the moment when hardship
and fatigue reach their climax, from the commander of the
unit down to the last man. At this time, if everyone is determined
to carry out the unit commander's orders without hesitation, and
if the platoon commander advances at the head of his
men, the spirit of daring and solidarity aroused in the company
will enable them to penetrate the enemy position.
"After victory, tighten your helmet strings" (an old Japanese
proverb). After fierce fighting, or during a pause in the battle, the
mind is apt to relax. This is the most dangerous moment. Even
men who are daring and determined during a charge have
a tendency to be cowardly as soon as the fighting changes to
mopping-up operations, and only scattered fire and small numbers
of enemy troops are encountered.
c. Use of Machine Guns
In a naval landing party (Marines), there is virtually no
necessity for a machine-gun company. It is preferable to
include in each company a machine-gun platoon under the command
of the rifle company commander. From the nature of a
naval landing party, there is practically no occasion on which
a machine-gun company joins in the action as an independent
unit with its six machine guns. As a rule, each platoon is
detached, and is organized under the rifle unit company commander.
This is particularly true in the case of street fighting
and fighting at close quarters. Even if a machine-gun company
were independent, it would be difficult for it to put up a vigorous
fight without the support of the rifle units. Nowadays machine-
gun squad training is the main consideration in machine-gun
training, and the need for machine-gun company exercises is not
All machine-gun personnel, with the exception of the gunner,
must be armed with rifles. This is especially necessary in street
fighting, fighting at close quarters, and so on. Even when
attacking and advancing, the carrying of rifles never impedes
the advance. In case of an enemy attack, it is easy to make a
sortie with the machine-gun ammunition personnel. The ideal
rifle for machine-gun personnel is the 1911 model carbine, which
is nearly 12 inches shorter than the 38-year type, model 1905.
The gun loopholes of a position must always be screened with
pieces of cloth or matting. If the enemy can see through them, his
snipers may fire at them, or he may concentrate his fire on
them. This is particularly necessary in the case of openings for
heavy machine guns, which must be large on account of the angle
Even when an action is going on, arms must always receive
proper care; otherwise numbers of such arms as rifles, care of
which is apt to be neglected, will be found red with rust. It
must be impressed upon the men that exchanging fire with the
enemy, is not the only battle—taking proper care of arms is a
great battle in itself.
7. NOTES ON DEFENSE
This "Outline on Defense" was dated Sept. 1, 1942, and was
distributed on at least one Southwest Pacific Island.
Special attention should be given at this period to the following
matters concerning defense:
a. Selecting a Position
When selecting a defensive position, bear in mind that the
enemy in attacking may not establish an extensive field of fire,
but may concentrate fire power in a surprise attack from extremely
close range. Special consideration should be given to
concealment from the air.
The enemy will approach through the jungle and may attack
from all sides, especially from the rear. As a counter measure,
deploy all units, from squads to regiments, in circular formation,
changing the original frontal positions as the enemy advances.
Utilize oblique and flanking fire to the fullest effect.
(1) To the extent that time permits, construct strong defensive
works, including shelter if possible. (Australian methods are
(2) Provide positions for grenade dischargers, light machine
guns, machine guns, and other appropriate heavy firearms. Depending
on the enemy situation, either fire in the anticipated direction
or hold your fire to avoid disclosing your positions and
(3) Various types of obstacles should be constructed within
the jungle where they will be least expected by the enemy, thereby
affording opportunity to strike the enemy at selected places.
(4) Establish ammunition dumps in locations affording maximum
protection from detonation by enemy bombs. When storing
large amounts of ammunition, construct dumps in several
(5) Endeavor to deceive the enemy by constructing dummy
loopholes, dummy soldiers (with steel helmet, knapsacks, and
so on), and dummy trenches.
(6) Each squad should look after its own water containers, making
full use of empty cans abandoned by the enemy.
d. Various Other Preparations
(1) Use every means to secure as much ammunition as possible. The
company in particular should utilize captured weapons to the
best advantage (especially automatic rifles, captured ammunition, and
(2) Consider the fire sectors covered by rifles, light machine
guns, hand grenades, and so on. Do not omit the preparation of hand grenades.
(3) Allow the enemy to approach very close, then fire calmly at individual targets.
(4) Use ammunition sparingly if it should become scarce.
(5) Do no make a sortie or counterattack heedlessly, simply because the
enemy has approached. Such actions may have immediate advantage but
casualties will soon result, and it will be difficult to maintain the
position. Remain calm as the enemy approaches, and fire to annihilate.
(6) Pay close attention to sanitation, considering the length of
time your position will be occupied.
(7) Make certain that adequate provision is made for drainage of quarters, water
supply installations, lines of communication, and so on.
(8) In the absence of the enemy, assign one section as lookouts.
8. INSTRUCTIONS TO LANDING PARTIES
a. When Opposed
When opposition is expected, it is best to begin operations before
dawn so that occupation is possible at dawn.
Make your landings with the boats in column formation. Or, if the
situation demands, use the line formation.
If the landing point is steep, dash under the position so that you
will be under the angle of fire.
b. Procedure After Landing
(1) All white troops and police will be captured. In case they resist, they
will be killed by shooting and bayoneting.
(3) All white persons and Chinese (including women and children) will be
thoroughly searched and all arms confiscated. They will be assembled and
confined in a suitable place.
(3) As it is difficult to distinguish Germans and Italians from other
whites, they will all be confined together.
(4) Native policemen will be disarmed and confined; however, since they
are to be used later for police work, they should be treated with consideration.
(5) In case there are any Japanese, they should be released at once.
(6) Beware of small land mines, especially in the vicinity of the pier.
(7) Do not stupidly drink water or eat anything, as it may be poisoned.
(8) Installations, machinery, goods, and so on will be used later, so do not
willfully destroy them.
(9) All radio equipment will be confiscated.
(10) When searching persons, all notes and other written documents
must be confiscated, and their contents inspected. The
necessary steps will be taken so that at a later time the holder of
each document may be identified.
(11) Be especially careful not to destroy furniture, water tanks, ice
boxes, safes, and so on.
(12) Cans of food and other useful things should not be punctured
with the bayonet in order to inspect them.
(13) It is forbidden to waste food and other material willfully.
9. SECURITY MEASURES
Concerning the secrecy of the battle plan, the following items
must be understood thoroughly:
a. During the daytime, there should never be any cooking;
b. Absolutely do not expose any bright lights, even though you
are handicapped by darkness;
c. Do not throw any fording materials in the river;
d. Do not talk loudly;
e. Since the natives in this area are not trustworthy, soldiers must not
discuss troop movements;
f. Do not use native roads;
g. Do not say "Oi Oi" (English equivalent of "hello"), as this shows that
one is not well mannered.
10. REGARDING U.S. SOLDIERS
a. They do not like the jungle at night;
b. They fear our night attacks, especially our battle cry;
c. They use grenades within their positions;
d. Their artillery uses one "leading" shell out of every five shells;
e. They do not make sorties while in a defensive position, and
they respect our fire power.