A ninja (Japanese: 忍者, lit. 'one who is invisible'; [ɲiꜜɲdʑa]) or shinobi (Japanese: 忍び, lit. 'one who sneaks'; [ɕinobi]) was an infiltration agents, mercenary, or guerrilla warfare and later bodyguard expert in feudal Japan. They often employed in siege espionage missions, and Military deception,. They were often appeared in the historical records during the Sengoku period, antecedents may have existed as early as the 12th century.
During the Japan's warring state period, jizamurai clans of peasant-warriors in Iga Province and the adjacent Kōka District formed ikki – "revolts" or "leagues" – as a means of self-defense.
Following the Tokugawa shogunate in the 17th century, the ninja faded into obscurity. A number of shinobi manuals, often based on Chinese military philosophy, were written in the 17th and 18th centuries, most notably the Bansenshūkai (1676). (Full article...)