A, or was a spy and infiltrator in pre-modern Japan.[1] Antecedents may have existed as early as the 12th century. Current legends to the contrary, there is little evidence that they were assassins.[1]
In the unrest of the Sengoku period, the jizamurai, peasant-warriors in Iga Province and the adjacent Kōka District, formed ikki – "revolts" or "leagues" – as a means of self-defense. They became known for their military activities in the nearby regions and sold their services as mercenaries and spies. Following the Tokugawa shogunate in the 17th century, the ninja faded into obscurity.
Ninja is the on'yomi (Early Middle Chinese–influenced) reading of the two kanji "忍者". In the native kun'yomi reading, it is pronounced shinobi, a shortened form of shinobi-no-mono (忍びの者).[2]
The word shinobi appears in the written record as far back as the late 8th century in poems in the Man'yōshū.[3] [4] The underlying connotation of shinobi (忍) means "to steal away; to hide" and—by extension—"to forbear", hence its association with stealth and invisibility. Mono (者) means "a person".
Historically, the word ninja was not in common use, and a variety of regional colloquialisms evolved to describe what would later be dubbed ninja. Along with shinobi, these include monomi ("one who sees"), nokizaru ("macaque on the roof"), rappa ("ruffian"), kusa ("grass") and Iga-mono ("one from Iga"). In historical documents, shinobi is almost always used.
In modern fiction, is also another word used to describe ninja, specifically female ones. It was originally argot for "woman".[5] It supposedly comes from the characters く (ku), ノ (no), and 一 (ichi), which make up the three strokes that form the kanji for .
In English, the plural of ninja can be either unchanged as ninja, reflecting the Japanese language's lack of grammatical number, or the regular English plural ninjas.[6]
Despite many popular folktales, historical accounts of the ninja are scarce. The social origin of the ninja is seen as the reason they agree to operate in secret, trading their service for money without honor and glory.[7] The first dubbed ninja was a man named Otomono Sahito, though historical evidence of his existence is scarce.
However, some ninjutsu books described specifically what tactics ninja should use to fight, and the scenarios in which a ninja might find themselves can be deduced from those tactics. For example, in the manuscript of volume 2 of Kanrin Seiyō (間林清陽) which is the original book of Bansenshūkai (万川集海), there are 48 points of ninja's fighting techniques, such as how to make makibishi from bamboo, how to make footwear that makes no sound, fighting techniques when surrounded by many enemies, precautions when using swords at night, how to listen to small sounds, kuji-kiri that prevents guard dogs from barking, and so on.[8] [9]
The title ninja has sometimes been attributed retrospectively to the semi-legendary 2nd-century prince Yamato Takeru.
Prince Shotoku, who lived from 574-622 AD, was believed to have employed a ninja spy named Otomono Sahito.
In the Kojiki, the young Yamato Takeru disguised himself as a charming maiden and assassinated two chiefs of the Kumaso people.[10] However, these records take place at a very early stage of Japanese history, and they are unlikely to be connected to the shinobi of later accounts. The first recorded use of espionage was under the employment of Prince Shōtoku in the 6th century. Such tactics were considered unsavory even in early times, when, according to the 10th-century Shōmonki, the boy spy Hasetsukabe no Koharumaru was killed for spying against the insurgent Taira no Masakado.
The history of Ninjitsu schools recorded around the 12th century, when Daisuke Togakure and Kain Doshi formalized the teaching of Chinese and native Japanese guerilla tactics to which was as counter-culture of the time. As a samurai, Daisuke lost his lands and title after being defeated in a regional conflict. Refusing to commit Seppuku, Daisuke travelled to the mountains of southwest Honshu in 1162. Here, he met Doshi, a Chinese warrior-monk. Daisuke abandoned his way of bushido, and worked with Doshi to formulate the guerilla art of war called ninjutsu. Daisuke's descendants founded the first ninja-ryu, or ninja school, the Togakureryu.[11]
Later, the 14th-century war chronicle Taiheiki contained many references to shinobi and credited the destruction of a castle by fire to an unnamed but "highly skilled shinobi".
It was not until the 15th century that spies were specially trained for their purpose. It was around this time that the word shinobi appeared to define and clearly identify ninja as a secretive group of agents. Evidence for this can be seen in historical documents, which began to refer to stealthy soldiers as shinobi during the Sengoku period. Later manuals regarding espionage are often grounded in Chinese military strategy, quoting works such as The Art of War by Sun Tzu.
By the Sengoku period, the shinobi had several roles, including spy (kanchō), scout (teisatsu), surprise attacker (kishu), and agitator (konran). The ninja families were organized into larger guilds, each with their own territories. A system of rank existed. A jōnin ("upper person") was the highest rank, representing the group and hiring out mercenaries. This is followed by the chūnin ("middle person"), assistants to the jōnin. At the bottom was the genin ("lower person"), field agents drawn from the lower class and assigned to carry out actual missions.
See main article: Iga ikki, Kōka ikki and Iga–Kōka alliance. The Iga and Kōga "clans" were jizamurai families living in the province of Iga (modern Mie Prefecture) and the adjacent region of Kōka (later written as Kōga), named after a village in what is now Shiga Prefecture. From these regions, villages devoted to the training of ninja first appeared. The remoteness and inaccessibility of the surrounding mountains in Iga may have had a role in the ninja's secretive development. The chronicle Go Kagami Furoku writes, of the two clans' origins:
Likewise, a supplement to the Nochi Kagami, a record of the Ashikaga shogunate, confirms the same Iga origin:
