A Short Study of Terms as Indicators of the Historical Role of Japan's Special Warriors


There are various channels of investigation which one might choose to shed some light on the otherwise elusive topic of the special warriors of Japan commonly known today as ninja. The one I would like to offer here focuses on some of the terms used throughout Japanese history to refer to warriors who specialized in gathering information and who were skilled in a wide range, often uncommon, methods of warfare.

Some terms identified certain roles and duties, other terms did not point at any specific role, rather were coined by a leading warrior to distinguish his warriors, or espionage agents, from others. Such terms were similar to a local dialect in that they only used a term unique to that locality, but that in essence it was not unique. It is also important to point out that as warfare developed and became more sophisticated and complex, so was the variety of duties assigned to special warriors.

Before the Nara period (711-794) there seem to have been one or two terms regardless of the warriors duties. It is said that as early as the seventh century, Prince Shotoku have already used the term shinobi to describe a person who provided special services. In the case of Prince Shotoku, shinobi were his close attendants whom he used for various tasks, most likely as secret messengers or information gatherers. The most known among these shinobi was Otomo Komado. At that time the term shinobi was not written with the single character nin, rather a combination of three characters used for their sound alone. In fact, the meaning of the characters was completely unrelated to espionage, and put together produced no logical meaning. This early use of the term shinobi indicates that warriors specializing in espionage and covert warfare existed before the introduction of Chinese knowledge and terminology of warfare.

Though clear evidence is unavailable, it appears that Prince Shotoku also began to use the term kanja for experts of espionage. In fact, it is the earliest term for a person who specializes only in information gathering. The term kanja was the Japanese rendering of the Chinese term kan, adding the character for "person" or sha, which together with kan produced the term kanja.

A term similar to kanja that was also adopted from Chinese was kancho. The character cho means to look around for information, thus when combined with the character for kan produces a meaning identical to kanja. These terms are therefore interchangeable, with no specific connection to any particular historical event or period. Another derivative of kan was Emperor Tenmus use of sokkan for an espionage agent who also performed duties such as assassination. This was a personal attendant warrior for Emperor Tenmu by the name of Takomi, for whom there are references in historical records. Yet another Chinese term that was adopted in Japan was kansai, which meant a person who searches for detailed information.

Borrowing these Chinese terms was the result of a much wider trend of importing Chinese philosophy, religion, state institutions, and culture. Systematic knowledge of espionage arrived from China in arguably the most well known text on warfare written by the Chinese general Sun Tzu. In this work those engaged in espionage were divided to five types called gokan, or five spies. These included the local agent (gokan, using a different character for go), double agent (hankan), inside agent (naikan), expandable agent (shikan), and living agent (shokan). The gokan system in Japan served as the foundation for the Japanese use of information gatherers, and is mentioned in the Bansenshukai as the foundation for a more elaborate system developed in Japan. Thus, it appears that the Chinese contribution to the development of espionage in Japan has been rather substantial.

The Heian (794-1185) and Kamakura (1185-1333) did not produce any new terms worth mentioning here. However, since the Onin War (1467-77) and the increasing intensity of strife among local warlords produced a whole range of specializations associated with espionage and covert warfare. Some terms were common, others associated with the nature of the warriors duty, the region, or even the warlords personal preference.

Mitsumono (also rappa) was a system of three types of warriors who specialized in information gathering established by Takeda Shingen. Shingen who made extensive use of espionage employed warriors of low social status whom he called rappa. However, he divided the role of rappa to those specializing in collecting verbal information, and two types of observers. These three types became known as mitsumono, and together with the term rappa were used in eastern Japan.

Tan'en (also read nokizaru) was a term that reflected the skills of a warrior. It referred to one who specialized in entering a house through the roof. This warrior walked on the roof and jumped from rooftop to rooftop like a monkey leaping from tree to tree, hence its name nokizaru ("rooftop monkey"). These agents were known in the Sengoku period and served the warlord Uesugi Kenshin.

Some warrior bands skilled at special warfare were formed only to achieve a certain goal. After the goal was achieved the band was dispersed. For example, the nusumigumi ("thieves band") was a group of fifty Iga warriors serving Maeda Toshiie in strengthening his Kaga domain. Once the domain achieved stability and strength the group was dissolved.

Under certain conditions a warrior's specialty or purpose, or the warlords preference, became the terms used to identify such warriors. Kikimonoyaku was one who gathered enemy secrets by listening to rumors and gossip, but the origin of the term is unknown. On the other hand, kyodan, or an agent recruited from within the enemy troops by bribes such as money and wine, was a term first used by Oda Nobunaga in the Sengoku period (1477-1573). Kusa , or kusamono, were agents used by the Sanada family. The term was coined because these agents relied on hiding in fields and forests, or in peasant houses. The word kusa means grass, and kusamono is a "grass-person" and suggests "a person who hides in the grass."

Some warrior bands were independent of powerful warlords. Shinobi no shu was a group of warriors formed and supported by the Iga warrior Todo Takatora sometime during the Keicho era (1596-1614). This group was one of five called Iga musokunin, which comprised five bands of warriors each specializing in a certain aspect of warfare. When Commodore Perry first arrived in Uraga bay in 1853, one of those warrior musokunin, Sawamura Jinzaburo, ran to Uraga to spy on Commodore Perry's Black Ships.

A similar independent type of warriors were the suppa (also seppa) of western Japan. The term meant to pass through, unsheathe, excel, but also referred to a thief or brigand. A known suppa in the early modern period was Fuma Kotaro. His lineage and knowledge, however, are unknown. There were two types of suppa: yaburi-suppa and kakae-suppa. Both were at social status of thieves and mountain brigands.

The Tokugawa shogunate (1600-1868) further qualified the use of espionage and skilled warriors. For example, akeyashikiban was a guard system used by the third Tokugawa shogun Iemitsu. When the shogun or daimyo were absent from their castle and the castle had to remain empty, a group of Iga warriors was assigned to guard the castle until the shogun or daimyo returned with their regular band of warriors.

Most of the new developments were related to the shogunate's mechanism of state control. Onmitsu was a term coined by the Toyotomi family but onmitsu played an important role only later under Tokugawa rule. The Tokugawa shogunate used onmitsu for gathering information throughout Japan. Unlike the metsuke and ometsuke officials whose duty was similar to that of the onmitsu, the onmitsu traveled in the domains incognito while the metsuke and ometsuke were recognized officials.

Another mechanism of control involved the use of kobushikata. These were agents who were part of a group of ten under the command of a group of three Iga warriors who worked in the service of a local official. The kobushikata agents usually performed manual labor such as road repair and construction, and it was in this disguise that they performed their duties spying on the local population.

While it is possible to identify the origin and use of most terms associated with Japan's special warriors, the origins of the term ninja, the most recent term of which almost any informed child is familiar with, remains unknown. Some scholars have speculated that it was coined by performers and entertainers during the late Tokugawa period, others "blame" the modern entertainment industry. At this time, the lack of reliable sources to point us to the origins of the term ninja seem to remain unresolved.

(Primary sources for this article include: Sonshi and Bansenshukai. Secondary sources include: Tobe, Shinjuro, Ninja no nazo: sengoku kage no gundan no shinjitsu; Nawa, Yumio et. al., Shinobi no mono 132 nin deta fail; Okuse, Heishichiro, Ninjutsu: sono rekishi to ninja.)