A brief history of samurai warfare

The samurai – technically servants of the empire but in reality the military ruling class – are highly romanticised figures. Little is known about the complex realities of their world; with only a handful of samurai texts available in translation, the warriors have been mainly viewed through the foggy lenses of war chronicles and epic tales that describe their early battles. One such example is the story of the double death of the 14th-century warriors Kusunoki Masashige and his brother Masasue – who committed suicide together following their defeat at the battle of Minato River. When Masashige asked his brother for his last wish, Masasue replied that he vowed to be reborn seven times over in service of the emperor Go-Daigo. Although it’s a fascinating tale – a testimony to imperial devotion – it reveals little about the practicalities of samurai warfare.

In the first stages of the samurai era, from the 12th century and up to the late 15th century, warfare was characterised by highly mobile cavalry-archer units. Early battles were conducted predominantly on horseback. Great phalanxes and spear divisions were added into the mix over the course of the Middle Ages, with a final concentration on guns in the latter half of the 16th century. Following the battle of Sekigahara in 1600, which many believe to be the start of the lockdown of Japan by the Tokugawa family, warfare was studied mostly for its principles. These were the days of peace, marked only by small conflicts.

To discover how the samurai actually lived and fought in more detail, it is necessary to look at the very few available translations of early 17th-century manuscripts that recorded the tactics used in the great battles of the Middle Ages. The following guide to real samurai warfare is based on these little-known historical documents.

Orders for war

The samurai tended to live on the land of which they were overlords, maintaining their own martial family traditions – such as castle building, gunnery, cavalry and even a mixture of astronomy and astrology – while awaiting orders for war. Upon receipt of such orders, the samurai would proceed from their fortified manor houses, flying their personal banners and ancient family emblems, and bringing with them their assistants: men-at-arms, grooms, sandal boys, spear bearers, and other aides of war.

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The leaving ritual for each warrior involved the ceremony of nine cups, during which certain foods were consumed – including the sea snail uchiwabi (abalone). Word-play was used to promote victory for the allies and death to the enemy. As the warriors left the stronghold, no women were allowed in view of the men, for women were believed to have yin energy while Japanese war required yang, or ‘male’, energy. It was for this reason that soldiers stepped off with the left leg when they moved out to war, as this leg was of the element of yang and male power. Finally, the samurai left their gates with a ritualistic chant.

Armour and equipment

Samurai armour had to be attuned with the five Taoist elements: wood, fire, earth, metal and water. Helmet type, the colour of laces and plates, the bamboo banner pole, and even the colour of the horse had to be in unison with the ‘Cycle of Creation’ in the theory of the five elements – and not in a ‘Cycle of Destruction’. Thus, a colour that represented water should not be matched with a colour that represents fire – and so on. In the samurai’s view, those who aligned all of these elements would correctly draw on the power of the fundamental building blocks of the universe and channel divine supremacy in war.

Samurai loin cloths – and, indeed, all the knots on their armour – were tied to the front in the tradition of someone who was dead (tying to the back was reserved for the living). By dressing the same as a corpse, the samurai was therefore prepared for a possible journey to the afterlife. A samurai who was extremely committed could also cut the cords of his armour – which held the different pieces together – so they were so short they could only be knotted once, a style known as ‘the costume of death’. With the cords tied so closely together, he would be unable to retie them again. The act symbolised the samurai’s intention not to come back alive, should the battle not go well.

In the samurai’s quiver, a set of arrows with a single shaft was locked in place. It was never to be fired in life, but would accompany the samurai to the underworld should he die. The samurai’s gloves were called ‘the gloves of hell’ and the kneecaps of his greaves were named ‘the crown of hell’. Small, cloud-like decorations on the rim of his helmet denoted a boundary between the human world and heaven, and on the helmet, at the very apex of the armour, was a hole – the ‘vent to the sky’ – in which the great serpent god of war with 98,000 scales was believed to descend and empower the warrior for battle. In short, samurai armour was thought to be a powerhouse that channelled divine power.

Preparing the troops

Esoteric tacticians called gunbaisha debated the most auspicious day for the army of samurai to leave, each arguing that his own family system was correct. As the factions within the samurai army jostled for positions of power, rules of obedience – such as no raping or theft – were set in place; rewards of land or gold were outlined; words of weakness avoided and only bellicose language was used. The samurai were divided into two columns formed of 12 separate sections: scout groups were positioned at the front with a flag section; the command group was located in the centre, and the well-defended pack train formed the rear.

The army then paused outside a place of worship dedicated to the god of archers, Hachiman Daibosatsu (a Shinto deity who follows the way of Buddha). There, the flags of the army were unfurled and dedications given. Once the forces were blessed, the army advanced out of its own domain to war, with spear and helmet bearers close to their masters as they entered enemy territory.

Gathering information

By this point, ninja – the samurai army’s Special Forces – had already returned with detailed maps of the area, as well as information about the enemy generals (such as their crests, family connections and signatures). Some will have stayed within the enemy area to be hired as mercenaries in order to attack the enemy population from within, if needed, and spread propaganda. At this stage, the army on the march would send out advance parties of highly trained and high-ranking scouts to pick out the best places to encamp – calculating the necessary land area, water usage and exit points, and studying the weather and the moon to avoid inundation by flood or high tide ­– and of course searching for the enemy forces as the lumbering army made its way through the landscape.

Encampment

Each night the army would arrive at an area already marked out with flags, where they erected marquee-like tents with pre-made detachable poles and waterproofed paper roofs. A virtual town was created, complete with paths and restricted areas, all encompassed by banks and ditches outside a bamboo wall. As darkness fell, the camp torches were lit and each tent was illuminated by candles held on suspended horse stirrups. Outside the camp, listening scouts and smelling scouts sat in wait for enemy infiltrators or attackers.

The field of battle

After a prolonged shadowing, during which the samurai army and the enemy army each tried to gain the upper hand, the forces would meet. Now the samurai had to control their retainers as the “wave of fear” – as they called it – passed over their men. Once settled, the forces arranged themselves on the battlefield – foot soldiers and archers to the front, with the samurai vanguard close up behind them. The signal drums were beaten, the flags waved their signals and the conch shells sounded out. Oaths were taken in which wives and households were forfeit for desertion, while ‘kill squads’ were formed as teams of three, to target single opponents. The archers would let loose their volley, while the foot soldiers protected them; upon command they would break left and right, allowing the fearsome samurai vanguard to charge forward, the bravest of which tried to gain the most prized of samurai honours: to be the ‘first spear’, which is to be the first into actual combat. The first kills were made and enemy heads were taken, the two sides would burst into each other, while the foot soldiers and archers flanked and lent aid, and the commander-in-chief sat with his command group relaying orders through flags and drums. Eventually the lines blurred and it would become difficult to keep the forces coherent. If the samurai were victorious, light skirmishes would ensue as teams of samurai hunted down those hiding. Finally the signal was given for all to return to the command group.

Post-battle ceremony

Inside the command centre was the ‘turret of arrival’, a place where the lead secretary – an important man – recorded the deeds, the dead, the injuries, and enemy heads in separate ledgers. Care was taken lest he incorrectly recorded who took the first head, so candidates who claimed this honour were interviewed and their stories checked, with times of travel and start times for separate conflicts taken into consideration. Heads were identified if possible, as rewards in the form of land allowances were greater the higher the class of soldier killed, and some devious samurai may use stolen helmets to pass off the heads of ordinary soldiers as those of higher-ranking samurai. Those who had not made a kill may have been tempted to slay women and monks in the nearby area to use their heads instead, and for this reason, when the order came to only take noses (instead of heads) as proof, the protocol was to skin the face to include the moustache or facial hair as evidence that it was a warrior that has been killed. Finally, the ceremony of the head inspection was performed: the commander-in-chief inspected a certain number of heads, under the spiritual protection of archers and tacticians to ensure that vengeful ghosts did not attack.

Returning home

When the war was over, the army returned home. Promises kept were rewarded, wealth gained was distributed, promotions were given, new land was settled, wives and children were greeted, the dead were mourned and celebrations and ceremonies were had by all. The gods were praised, for victory had been achieved.

Antony Cummins is the author of Samurai Arms, Armour and the Tactics of Warfare (October 2018), published by Watkins.

About the historical texts

This guide is based on a work by Natori Sanjūrō Masazumi, who is well known in the samurai history community, primarily for his 'Shoninki', or 'True Path of the Ninja' – one of the most reliable records about the famous Japanese spies. His incredibly detailed military study manuals, written around the 1670s and until very recently lost on library shelves, have only recently come to light but offer a wealth of information on the strategies of the age of war. In life he was a military teacher to the samurai of Kii domain and a personal retainer of one of the most powerful men in Japan, Tokugawa Yorinobu, son of the famous Tokugawa Ieyasu, the famous unifier of Japan.