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Ninja History 101: Spies and Assassins

Updated: Nov 20, 2023


Ninja History 101: Spies and Assassins
Ninja History 101: Spies and Assassins

As Heichichiro Okuse says, it was cunning and deception that gave the ninja the edge over their enemies. These traits were emphasized and sharpened during ninjutsu training. The ninja raised espionage to a highly developed art centuries before such training was given to cloak-and-dagger agents in Western countries. There were three main categories of ninjutsu training for espionage: toiri-no-jutsu, or the tactics of sneaking into an enemy's camp; chikairi-no-jutsu, or infiltrating enemy lines after the outbreak of hostilities; and ongyo-jutsu, or the ruses of escape.


Ninjutsu Training Type #1: Toiri-no-jutsu

The Iga school ninjutsu, one of the greatest ever developed, trained its members in 11 different toiri tactics for breaking into the enemy's camp. The first of them was called shikei-no-jutsu, or careful preparation for achieving one's aim.


For instance, take a case where a ninja was handed the dangerous assignment of assassinating an enemy lord. The lord would be heavily guarded, both by samurai and his own ninja. It might be far too risky to attempt a frontal attack or a midnight break-in. With such difficult assignments, the ninja might fall back on cunning.


In such a case, the ninja might proceed indirectly. He might, for instance, try to secure work at a local Buddhist temple. After winning the priest's confidence by hard and dedicated service, he would get the priest to recommend him to the lord as a servant. He would thus gain entrance to the lord's house through the front door, and when the chance presented itself, assassinate him.



Katsurao-no-jutsu was a similar tactic. It involved sending secret agents for high official placement among the enemies. There were other counter-espionage practices developed for sending in spies and recruiting accomplices among the servants employed by an enemy agent.


One of the more interesting aspects of the toiri tactics was the use of female agents, who were the feudal-age Mata Haris of Japan. Samurai and others in the employ of an enemy lord might be tempted with women or plied with liquor and money in order to win them over.


Ninjutsu Training Type #2: Chikairi-no-jutsu

The second category of espionage tactics was concerned with infiltrating enemy lines during battle. In such cases, the ninja acted in a role similar to that of the British commandos of World War II, sneaking behind enemy lines to disrupt their position and engage in guerrilla tactics.


Geinyu-jutsu tactics involved such pleasantries as ambushing enemy soldiers, setting fire to their camp, stealing their supplies and setting false rumors afloat. In suigetsu-jutsu, ninja disguised themselves as enemy troops, mingling with them and causing confusion by any means possible. Joei-nin included ruses of sneaking into an enemy castle or camp at night when the main forces had left or when the troops were too exhausted to be alert.


Hoka-jutsu was concerned with burning enemy installations, using as targets powder dumps, armories, warehouses, etc. It was important to set fire to as many places as possible at the same time to increase confusion.


Ninjutsu Training Type #3: Ongyo-jutsu

The third category involved escape. Here, the ninja gave full rein to trickery and stealth and gained the reputation of being superhuman. They were said to be able to disappear through walls, turn themselves into trees or rocks and live underwater like a fish. All of these had logical explanations, of course.

Ongyo-jutsu was divided into two categories: those for hiding (inpo) and those for disappearing (tonho).


The ninja were skilled at the art of camouflage. They would practice controlling their movements and holding positions for a long time so they might take on the appearance of a small tree or bush in the moonlight. In essence, they tried to give up their identity as human beings and become one with the object they were trying to imitate.


Another intriguing aspect of this type of ninjutsu training was controlled breathing. They might so reduce their respiration rate that they would appear dead during a hasty inspection. This skill also allowed them to stay underwater for long periods and to breathe through reeds or bamboo shoots.

Other tactics included blowing dust in an enemy's eyes or momentarily dazzling him by exploding flashing balls or firecrackers. The ninja were also taught to make use of any natural objects that might aid their escape. Nothing was considered too remote to be used, and special tactics were developed for all sorts of things. For instance, doton-no-jutsu was designed for hiding in or behind ground objects, such as ditches, mounds, holes, stone lanterns and statues.



Carried to its extreme, doton-no-jutsu could also have its amusing aspects. For instance, during the war of the Imperial Restoration of 1867, a ninja hid his wife and mother from enemy troops by concealing them in a place where nobody ever dreamed of looking. He buried them up to their noses in sunken pots full of manure and then covered them with compost straw.


Another tactic that could produce a chuckle when the ninja told tales of their exploits involved jinton-no-jutsu. This escape tactic involved the use of wit, disguises and small animals. Chased by guards, the ninja might pull a snake or frog out of their pocket and toss it at their pursuers, startling them for an instant. But an instant was all they needed to make good their escape.


Did we overlook any obvious ninjutsu tactics? Is manure really the best place to hide your loved ones? Let us know what you think in the comments section.





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