Ninja (忍者) or shinobi (忍び) were men who were trained for assassinations or covert operations in feudal Japan. According to legend, these mercenaries became active in the late Heian Period in the mountains around Kyoto, where ninja were sometimes confused with yamabushi (山伏, Buddhist ascetics, mainly of the Tendai-shū sect, living as hermits).

Ninja were recruited from among peasants from Kōga (甲賀) and Iga (伊賀) provinces (modern-day Shiga and Mie prefectures), where entire villages were devoted to these activities. Starting from the fifteenth century, they were mainly used by the daimyō to assassinate their enemies and penetrate their fortresses and castles.

There were three classes of ninja:
  • jōnin (上忍): the highest-ranking ninja, commanding operations
  • chūnin (中忍): responsible for preparations
  • genin (下忍): lowest rank, executing the missions
They were experts in all sorts of disguises, in the form of priests, monks, merchants, or fortune-tellers and – according to myth – wore black garments (忍び装束, shinobi shōzoku) during their nocturnal missions.

Experienced in all sorts of tricks and acrobatics, they used a wide variety of "non-noble" or unconventional weaponry to achieve their ends:
  • daggers
  • poison
  • iron claws (手虎)
  • darts (手裏剣 shuriken, 車剣 shaken)
  • incendiary and smoke bombs, etc.
A kunai (苦無) is a multi-functional weapon possibly derived from the masonry trowel.A shuriken (手裏剣, literally: "sword hidden in hand") is a concealed weapon that was generally used for throwing and sometimes stabbing or slashing.A shinobi-kama (忍び鎌) is a sickle that was generally used for cutting ropes, climbing obstacles, and could easily be hidden.A variety of shuko (手甲), tekko-kagi (手甲鉤) were glove-like hooks worn over the palm or on the back of the hand.

When their services were no longer needed during the Edo Period, many ninjas became pirates and assassins for hire. In an attempt to eradicate them, Oda Nobunaga sent a force of 46,000 men against them in Iga in 1581, of whom, the legend has it, 4,000 were killed.

Ninja, now the stuff of legend, have been the subject of many films, novels, manga, and practitioners of martial arts have created ninja schools (although not for assassination) to develop specific physical attributes among their followers, creating a sort of magical mysticism around them. This has nothing to do with the real ninja, but it is good marketing. Their "art" is called ninjutsu (忍術), nimpō (忍法), or shinobi, and their followers are ninjutsu-ka. Ninja were also sometimes referred to as iga-mon.


  • Nussbaum, Louis-Frédéric, Japan Encyclopedia, Harvard University Press 2005
  • Turnbull, Stephen (2014) "Ninja: An Invented Tradition?" , Journal of Global Initiatives: Policy, Pedagogy, Perspective: Vol. 9: No. 1, Article 3


Ninja and some of their equipment (image credit)