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Ninja

covert agent, mercenary, or guerrilla warrior in feudal Japan

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionSep 20, 2026
Entity authorityQ9402
Source-derived summary

A ninja (忍者; English: , Japanese: [ɲiꜜɲ.dʑa]), shinobi no mono (忍の者; Japanese: [ɕi.no.bʲi no mo.noꜜ]) or shinobi (忍び; Japanese: [ɕi.no.bʲi]) was a spy and infiltrator in pre-modern Japan. Antecedents may have existed as early as the 12th century. Despite popular belief, there is little evidence that ninja were assassins.

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 establishment of the Tokugawa shogunate in the 17th century, the ninja faded into obscurity.

Etymology

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).

The word shinobi appears in the written record as far back as the late 8th century in poems in the Man'yōshū. The literal meaning of shinobi (忍) is "to steal away; to hide" and—by extension—"to forbear", hence its association with stealth and invisibility.

Editorial summary

The public source identifies “Ninja” as covert agent, mercenary, or guerrilla warrior in feudal Japan. This brief keeps that definition visible, then builds a research path around Ninja, covert and agent.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current 186-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. Its value is orientation rather than verdict, with Ninja, covert and agent providing the first useful test.
Editorial analysis

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A short description can identify a subject without explaining its stakes. For “Ninja”, the useful work is to connect “covert agent, mercenary, or guerrilla warrior in feudal Japan” to the records capable of establishing context and consequence.

Evidence profile

Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 20, 2026. The linked authority identifier is Q9402. None of the 0 selected statements returned an explicit reference.

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A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

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Source & attribution

This entry incorporates text from Ninja” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.