Ninja AD 1460–1650

Secret operations, from guerrilla warfare to the murder of prominent rivals, are topics that may be found throughout Japanese history, but it is only from about the mid-15th century onwards that we find references to such activities being carried out by specially trained individuals who belonged to organisations dedicated to this type of warfare. Much of the activity is focused around the Iga and Koga areas of central Japan, so this location and time period will provide the major setting for this book.

The traditional view of the ninja as a secret, superlative, black-coated spy and assassin derives from two different roots. The first is the area of undercover work, of espionage and intelligence gathering (and even assassination) that is indispensable to the waging of war. The second is the use of mercenaries, whereby the leaders of military operations pay outsiders to fight for them. In Japan these two elements came together to produce the ninja and, curiously enough, the ninja provide almost the only example of mercenaries being used in Japanese warfare. Part of the reason for this was that secret operations were the antithesis of the samurai ideal. A daimyo (warlord) would not wish to have his brave and noble samurai’s reputations soiled by carrying out such despicable acts. Instead he paid others to do them. It was an unusual but highly valued service, and the Japanese historian Watatani sums up the situation as follows:
So-called ninjutsu techniques, in short are the skills of shinobi-no-jutsu and shinobi-jutsu, which have the aims of ensuring that one’s opponent does not know of one’s existence, and for which there was special training. During the Sengoku Period such techniques were used on campaign, and included sekko (spy) and kancho (espionage) techniques and skills.The term shinobi is merely the alternative reading of the character nin; hence shinobi no mono rather than ninja. But ninja trips more readily off a Western tongue, and has therefore become the popular term.

The ancestors of the ninja
As undercover operations are fundamental to the conduct of war in any culture, it is not surprising to read of such techniques being used throughout Japan’s own turbulent history, but the first written account confirms that even at that early stage such activities were somehow questionable, even when they produced results. In Shomonki, the gunkimono (war tale) that deals with the life of Taira Masakado and was probably completed shortly after his death in AD940, we read:
Over forty of the enemy were killed on that day, and only a handful managed to escape with their lives. Those who were able to survive the fighting fled in all directions, blessed by Heaven’s good fortune. As for Yoshikane’s spy Koharumaru, Heaven soon visited its punishment upon him; his misdeeds were found out, and he was captured and killed.

Spying was the classic ninja role, so we may note here the first written confirmation that such activities were perceived as contrary to samurai behaviour. Like Shomonki, the two greatest gunkimono, Hogen Monogatari and Heike Monogatari, were written for an aristocratic audience who wished to hear of the glorious deeds of their ancestors. The activities of the common foot soldiers, who outnumbered the mounted samurai by 20 to one in the armies of the time, are almost totally ignored, so it is not surprising that stories of ignoble undercover acts are conspicuous by their absence. The one exception is the story that begins Heike Monogatari, when Taira Tadamori thwarts an attempt to assassinate him by using the sort of trick later attributed to skilled ninja. Being warned beforehand that rivals in the Court intended his death:
… he provided himself with a long dagger which he put on under his long court dress, and turning aside to a dimly lit place, slowly drew the blade, and passed it through the hair of his head so that it gleamed afar with an icy sheen, causing all to stare open-eyed.

The bringing of weapons within the presence of the emperor was a serious offence, and Tadamori was ordered to give an account of himself, whereupon he showed that the knife was a dummy, but it had frightened off the assassin.

We hear nothing more of ninja-like activities during the decisive Gempei War of 1180–85. Instead it was conventional samurai warfare that established Japan’s first shogunate, the rule by a shogun (military dictator). The first family of shoguns was the Minamoto, and even though the Hojo family usurped them, the mechanism of military government helped ensure a century and a half of comparative peace in Japan.