Ninja

 The mercenary or covert agent of feudal Japan the Ninja (Ren Zhe, Japanese pronunciation: [nindza]) was known as Shinobi (Ren Bi, also known as [cinobi]). The responsibilities of a ninja included reconnaissance as well as espionage, infiltration ambush, deceit, bodyguarding , as well as their combat techniques in martial arts like Ninjutsu. The covert methods of fighting irregular wars were viewed as dishonorable and a detriment to the honor of the Samurai. Although shinobi in their proper form as specially trained spies and mercenaries, were introduced in the 15th century during the Sengoku period, [3] their antecedents could have existed from the beginning of the 12th century. In the turmoil of the Sengoku period, mercenaries as well as spies hired for hire began to operate within Iga Province and the adjacent region surrounding Koga. Koga. This is where the bulk of the information about the ninja comes from. After the unification of Japan under the Tokugawa Shogunate during the 17th century, the ninja faded into obscurity. [6] Many shinobi manuals were written in the 17th and 18th centuries. They are often based on Chinese military philosophical concepts.