Shadows of Medieval Japan

Specialized in espionage, sabotage, and assassination, ninjas, also known as shinobi, were covert operatives of medieval Japanese warfare. Trained extensively in martial arts, including what would later be termed ninjutsu or “the art of the ninja,” they remain prominent figures in contemporary media, embodying the archetype of the stealthy agent clad in black, executing missions with precision and disappearing without a trace. However, due to their secretive nature, historical facts about ninjas are as elusive as the figures themselves, with much of our knowledge derived from texts written long after the peak of the ninja era.

Originating possibly as early as the 12th century, ninjas came into prominence in the 14th century amidst Japan’s intense territorial disputes among daimyo (feudal lords). These lords mainly utilized ninjas for intelligence and counterintelligence tasks. Ninjas differed from samurai, Japan’s elite warriors, in both background and approach. They could come from any social level, not just elite families, and unlike samurai, they were not bound by a strict honor code, allowing them to engage in guerrilla warfare tactics considered dishonorable for samurai.

The archetypical ninja by Hokusai, 1817

The archetypical ninja by Hokusai, 1817

Many ninjas were ordinary people, such as villagers and farmers, who turned to stealth and even poison to protect themselves. Women, known as kunoichi, also joined their ranks, often infiltrating as dancers or servants to spy or assassinate.

Contrary to popular depictions of ninjas in all-black attire, historical evidence suggests they favored dark blue or persimmon for better night camouflage, as these colors were less visible under moonlight. This detail is supported by most of the surviving garments believed to have been worn by ninjas.

In terms of armament, ninjas preferred a shorter, less curved sword than the traditional samurai katana, which was better suited for tight spaces such as narrow castle corridors. They often carried these swords diagonally across their backs to facilitate unimpeded movement. In addition to mastering traditional Japanese weapons like swords, spears, halberds, and bows, ninjas had at their disposal an array of specialized tools designed for their covert operations. 

Ninja shuriken, throwing star

Ninja shuriken, throwing star

Among these were shurikens, or throwing stars. These multibladed steel stars, typically 20 cm in diameter with at least four points, were lightweight and did not hinder a ninja’s agility. Ninjas also employed fukibari or fukumibari, small metal pins concealed in the mouth and spat at adversaries, targeting the eyes for maximum effect.

Their arsenal also included more personalized tools like tekagi (metal knuckledusters) and hokode (hand claws), which doubled as climbing aids. When unarmed, ninjas relied on their formidable martial arts skills, honed through the study of ninjutsu, a discipline deeply influenced by Sun Tzu’s principles of guerrilla warfare. This connection is detailed in the Bansenshukai, a comprehensive ninjutsu manual from the 17th century that spans 22 volumes.

Ninja hokode, hand claws

Ninja hokode, hand claws

The term “ninja” only began to appear in historical texts in the 19th century, with “shinobi” being the more commonly used term in earlier periods. Shinobi were especially active during the turbulent periods from 1336 to 1600, playing pivotal roles in the Nanbokucho and Onin Wars and gaining prominence during the 15th-century Sengoku Jidai, or the age of the warring states.

The Iga and Koga Provinces, strategically located close to Kyoto yet sufficiently secluded, emerged as renowned ninja hubs. Clans hired ninjas from these areas as mercenaries, utilizing their expertise to gain and maintain territories during the prolonged Sengoku Jidai.

The plains of Iga, nested in secluded mountains

The plains of Iga, nested in secluded mountains

Despite their employment by various factions, ninjas’ stealthy nature meant many of their accomplishments went uncredited. However, a remarkable instance occurred during the 1560s Battle of Okehazama, where eighty Koga ninjas, under the command of Tokugawa, infiltrated and set fire to the towers of an Imagawa clan outpost, eliminating the leader and 200 soldiers.

The era of Sengoku Jidai underscored the high demand for skilled shinobi from Iga and Koga. Yet, Oda Nobunaga, a warlord who sought to unify Japan between 1551 and 1582, viewed the ninja strongholds as threats. While he quickly overcame the Koga ninja, the Iga region proved more challenging.

Oda Nobunaga, c. 1583

Oda Nobunaga, c. 1583

The conflict escalated into what became known as the Iga Revolt or Iga No Run, during which Nobunaga launched a decisive assault on the Iga clan with a formidable force exceeding 40,000 soldiers. This aggressive strategy forced the Iga ninjas to engage in direct combat, leading to their defeat and dispersion across neighboring regions.

Despite the destruction of their stronghold, the ninjas’ presence persisted. A number of them found service under Tokugawa Ieyasu, who became shogun in 1603. Even with their diminished numbers, ninjas continued to play roles in various conflicts. However, with the onset of the Edo Period and the establishment of peace under the Tokugawa Shogunate, the era of the ninja came to an end. Yet, the fascination with their skills, legends, and mystique continues to thrive in films, games, and comics, a testament to their enduring appeal in contemporary culture.

Editors’ finds

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Masterpiece spotlight

The fly by Hanno Karlhuber, 1984

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Words of wisdom

“The only person you are destined to become is the person you decide to be.” —Ralph Waldo Emerson

“The best and most beautiful things in the world cannot be seen or even touched—they must be felt with the heart.” —Helen Keller

“The best way to cheer yourself up is to try to cheer somebody else up.” —Mark Twain

“The mind is everything. What you think you become.” —Buddha


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