1. Ninja Basics
Ninja used to be called “Shinobi” and its existence was confirmed in the history records for the first time after the Northern and Southern Courts period (1336–1392) and is thought its origins is the villain resistance to the manor system which dominated in the second half of the 13th century.

Shinobi were called by various names depending on the regions, such as Rappa, Suppa, Kusa, Dakkou, Kamari and it was after the 30’s of the Showa era (mid 1950’s to mid 1960’s), the name Ninja was established. During the Sengoku period (late 1500’s to 1600’s), Shinobi were hired as mercenary troops by various parts of the feudal lords to intrude enemy systems, to set fire, to destruct, to night raid, to ambush and to collect information. However, the most important aspect above all was to convey the status of the enemy to the lord, and they needed to avoid combat as much as possible, in order to survive and go back to their masters.

Iga and Koga regions are close to Kyoto and are surrounded by a natural fortress of mountains. These topographic conditions helped autonomies to develop, to be armed, to form riots and weaken the feudal lord forces. Therefore, they were sometimes hired as mercenaries by neighboring countries to invade castles beyond the moat and to join battles.

Although Nobunaga Oda forces exerted a devastating blow to Iga and Koga autonomies, after the Honnō-ji incident on the 2nd date of the 6th month in the 10th year of the Kanei era, (June 21, 1582). Ieyasu Tokugawa escaped from Sakai (Osaka Prefecture) to his headquarters in Okazaki (Aichi Prefecture) Via Shirako (Suzuka, Mie Prefecture) beyond the Iga and Koga mountains, the Iga clans and Koga clans escorted Ieyasu Tokugawa in the mountains and fought the vanguards of Ieyasu in various battles. Based on these assistances, the Iga clans and Koga clans were granted Ieyasu Tokugawa's warrant.


2. The Course of Ninja History
When Ieyasu Tokugawa took reign and entered the metropolitan area of Edo on the 1st date of the 8th month in the 18th year of the Tenshō era, (August 30, 1590), the Iga clans and Koga clans also started to reside within Edo Castle town and in addition to securing Ōoku: The Inner Chambers and unattended mansions of the feudal lord, observing working conditions of the building plot, they also worked as espionage agents until the first year of Kan'ei era (1642).

Also they were organized into Koka-hyakunin-gumi: Koka Hundred-Member Gun Squad and Iga-hyakunin-gumi: Iga Hundred-Member Gun Squad as musket troops, taking turns on duty at hyakunin bansho: guardhouse for visitor inspections, to carry out the security of Ote-san-no-mon Gate: main entrance to the inner citadel, and were hired by the feudal lords.

It is described in “Gunpo Samurai Youshuu: dictionary of samurai martial law” that Iga clans and Koga clans were the best Shinobis.

In the peaceful era of Edo, their main tasks became to obtain information and to guard rather than to battle as well as to research the political situation in neighboring countries to take advantage of the its government.

Many people have an image of Ninja eavesdropping on conversation and lurking in the attic, but in fact in more occasions, they elicited information by becoming friends with local people.

At the middle of the 17th century, many books of Ninjutsu: the art of Ninja describing Shinobi’s techniques and frame of mind started to be published.

In the 4th year of the Enhou era (1676), from the sense of crisis that the techniques that had been passed down the generations among Shinobi would no longer be inherited, the “Bansenshukai“, in which ancient Chinese military treatise "Sun Tzu" and variety of manuals including the art of Ninja are woven into, was compiled by Sabuji Fujibayashi.

In this book “Bansenshukai“, devices such as climbing equipment, water equipment, opening devices, firearms and such are described with pictures, and in other books of Ninjutsu: the art of Ninja, they have a variety of descriptions including social skills, conversation techniques, mnemonics, transmission techniques, sorcerous, medicine, pharmaceutical, food, astronomy, weather, divination, gunpowder, thus Ninjutsu: the art of Ninja could be positioned as survival techniques based on comprehensive knowledge.

While actual Shinobi disappeared from the stage, Ninja started to be depicted with false images in novels and entertainment in the Edo period. In the early Edo period, Ninja were often depicted in a patterned story in which they come to steal valuables by using their Ninja techniques. One of the most known stories among them is the tale of Goemon Ishikawa.

Ninjutsu: the art of Ninja in those stories was beginning to be changed into mysterious art with the influence of Yojutsu magic. Yojutsu magic such as art of invisibility, flight, shadow cloning, resurrecting, channeling and transforming oneself into a toad, a rat, a spider, a butterfly and such further evolved under the influence of the Chinese novels. In result, Ninja who can disappear by holding a scroll with the mouth and making symbolic gestures with the fingers or could transform into a toad were born.

Also, in the late Edo period, images of Ninja shooting the shuriken: traditional Japanese concealed weapon wearing a black costume was formed through Kabuki and ukiyo-e.

During the Taisho period, a Ninjutsu boom broke out when “Sarutobi Sasuke” was published from Tatsukawa Bunko publisher. Tatsukawa Bunko enthralled their readership of apprenticeship boys, elementary and junior high school students by transcribing the narratives of kōdan performers into easy to understand and readable text with all Kanji characters given ruby text next to them as reading aid. Books dealing with Ninjutsu master such as “Kirigakure Saizō” and “Momochi Sandayū” were published one after another.

At the same time, “Jiraiya Gōketsu Monogatari: The Tale of Jiraiya the Gallant” starring Matsunosuke Onoe became a big hit. Children who were fascinated by the movie, tried to imitate Ninjutsu by jumping off from high places fracturing their bones, and by standing in front of the running trains caused them to stop. This evolved into a social problem.

On the other hand, the Taisho period was the time when there was a growing tendency trying to elucidate unknown things with scientific perspectives and many attempts were applied to rationally interpret Ninjutsu: the art of Ninja .

Gingetsu Itoh is one of the most famous to conduct studies with the perspective of how one can leverage Ninjutsu into modern society. Studies of Ninjutsu had been succeeded afterwards by Seiko Fujita, the 14th Headmaster of Kōka-ryū Ninjutsu who performed Ninjutsu himself, Heihichiro Okuse who served as the mayor of Ueno and others.


After the Second World War, works with Kunoichi: female Ninja had begun to appear. In “Bansenshukai“, it has been described that “bringing one kanji  character that requires (くノ一) writing (that is to say 女, female) into Shinobi“ as “Kunoichi jutsu”. It also stated that Kunoichi doesn’t necessarily perform the same tasks as male Shinobi, and these responded to the social advancement of women in the post-war era and Kunoichi had started to be depicted in various works.

Many Ninja novels were published from the end of 1950’s to 1960’s. “Fukurō no Shiro” by Ryōtarō Shiba, “Shinobi no Mono” by Tomoyoshi Murayama, “Ninpo Zenshu” by Yamada Kazetaro are some of the most important works. Movies like “Shinobi no Mono” and “Onmitsu Kenshi” became huge and Ninja who dressed in black costume, jumping over fences, running like the wind, rushing through without sinking under water, and shooting shurikens in quick succession had their time on the silver screen.

Ninja became incredibly popular material for children’s cartoons and accelerated its popularity even more after being broadcasted on television. Ninja tv shows reflecting the respective era such as “Sasuke”, “Kamui Den”, “Igano Kabamaru”, “Kamen no Ninja Akakage”, “Ninja Hattori-kun”, “Kagaku Ninja-tai Gatchaman”, “Nintama Rantarō” had been created.


3. Ninja Beyond the Borders
Ninja is also loved by many overseas starting with “Enter the Ninja (Moeyo Ninja)” with Sho Kosugi and Ninja movies were produced mainly in the United States. There are many young people who become a Ninja fan by watching animations and games like “Teenage Mutant Ninja Turtles” and “Naruto” and a great number of games and Ninja-related goods have been produced.

Ninjutsu tends to be captured as martial arts in overseas. Showing a deep interest in the Ninja may come from a longing for the "mysterious" existence of Ninja or from understanding the traditional values of Japan such as “Nin” for Ninjutsu is "Nin" of “Nintai - patience”. It is possible to say that Ninja spirit: even though one’s name would not be known to the world, one would endure and accomplish a mission with honesty and achieve a big job in the end, represents the Japanese way of life well. Aspects of Japanese culture such as technical capabilities, diligence, organizational strength and perseverance that have supported the modern Japanese society are compacted within some of the wisdoms of Ninja, and Ninja is the culture that represents Japan.