Date Masamune's Ninja Group? The Legend of the Kurohabaki-gumi [Part 1] | Did "Masamune's Intelligence Unit" that Appears in Mid-Edo Period History Books Really Exist?

Introduction

The Sengoku period—a time when armored warriors clashed in battle, utilizing their skills in swordsmanship, spears, bows, and horsemanship

This is a stereotypical portrayal, and it is well known that battles of that era involved a vast number of troop types and roles that cannot be described in such a simple statement

While the battles between warriors certainly represented one aspect of that era, the outcome wasn't determined solely by a pure test of strength

Therefore, "information" became extremely important .

In those times, when communication methods were limited, information about enemy forces was of such value that it could determine the fate of a nation. Quickly grasping national strength, military power, and signs of military action was a matter of great concern as it directly led to securing an advantage

It is said that the warlords of the Sengoku period used what are known as"ninjas".

The term is very well-known and could be replaced in modern terms with expressions like intelligence agent or spy

Although it is known that such individuals actually existed, their true nature as operatives means that the full picture remains unclear, and many episodes surrounding them are shrouded in mystery, remaining largely in the realm of legend

However, these stories can also be seen as evidence that information warfare, or espionage, played an important role for warlords during the Sengoku period, and there are numerous legends about ninjas that famous warlords relied on

One example is the "Kurohabaki-gumi," a type of gaiter said to have been used by Date Masamune, the one-eyed dragon .

In conclusion, this in itself is not considered to have high historical credibility, but it would not be unnatural for Date Masamune, who navigated the turbulent times with an exquisite sense of balance in both politics and military affairs, to have had ninja-like agents serving him

Therefore, in this article, I would like to provide an overview of the "Kurohabaki-gumi" as recorded in historical documents, and introduce what "ninjas" meant to Sengoku period warlords

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What is the Kurohabaki-gumi?

The "Kurohabaki-gumi"is said to have been a ninja unit founded by Date Masamune.

The name originates from theterm "habaki,"which refers to a type of garment wrapped around the shins to protect the feet and reduce fatigue from walking.

Later, it came to be called "kyahan" (leg coverings), and in modern Japan, it was commonly known as "gaiters."

The Kurohabaki-gumi (Black Leggings Group) is said to have worn matching leggings made of black leather, and this episode evokes the image of the Date clan's military uniform, which was unified in black

However, it remains questionable whether ninjas, whose profession relies heavily on secrecy, actually had a standardized uniform

The defining characteristic of the Kurohabaki-gumi's mission, as documented in historical records, is that they specialized in information warfare, such as espionage and disruption, rather than engaging in the use of force as combatants

Therefore, historical records indicate that they disguised themselves as skilled workers such as mountain ascetics or merchants, infiltrated various provinces, and carried out covert operations

historical records, Masamuneordered Abe Shigesada, the lord of Toriyama Castle in Shinobu County, who was in charge of intelligence gathering in southern Mutsu Province, to select 50 ninjas and appointed Yanagihara Tobei and Seze Kurōdo as their leaders.

Regardless of their social status, members were selected based on their aptitude as agents and their combat skills, and it is said that even those of peasant origin were employed with treatment equivalent to that of lower-ranking samurai

However, to reiterate, the likelihood of these being historical facts is low, and the prevailing view is that they are later creations or fabrications

It is unusual for ninjas, who are primarily intelligence agents, to be officially recorded in the first place, and even if Date Masamune used such groups, the details may not have been passed down, which is one reason why this is not the case

Next, let's look at this point in a little more detail

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Details of the literature describing the Kurohabaki-gumi

The main reason why the existence of a ninja group called "Kurohabaki-gumi" is considered unlikely to be historical fact is that there is absolutely no record of them in primary sources from the time when Date Masamune was alive

The first historical document in which his name appears, with a clearly defined date of creation, dates back to the mid-Edo period, meaning it was written more than 130 years after the death of Date Masamune

Furthermore, some documents have unknown origins, which makes it difficult to verify their historical value

Despite the nature of that document, let's examine how it refers to the Kurohabaki-gumi (black shag-toe group)

"Date Hikan"

This isMichitoki Handa, a, based on old records and traditions of the Date family, and was completed in 1770.

Here is a record of the Kurohabaki group

• They selected 50 people with the potential to become ninjas and hired them
• They infiltrated various provinces disguised as merchants, mountain ascetics, or other religious figures, and engaged in espionage

These points are mentioned

The text also states that the information obtained in this way was secretly given to Masamune, and that no one else knew about it

However, since it was written more than a century after Masamune's time, it is unclear how such important secrets were passed down through generations

As mentioned earlier, the name "Kurohabaki-gumi" cannot be found anywhere in the records from Masamune's lifetime, so it is reasonable to think that it was a later addition to the name

However, it must be acknowledged that we cannot rule out the possibility that Masamune may have employed spies or agents who could be considered ninjas

"Old Man's Accounts"

Another document that mentions the Kurohabaki-gumi is "Rojin Denmonki" (Records of Old Men)

Because this work is of unknown authorship and date of creation, it is the type of document that requires extreme caution when treating it as a historical source

This section goes into more detail about the composition of the Kurohabaki group

• The groups consisted of 50 and 30 people
• Those who excelled in close combat, such as swordsmanship and spearmanship, were selected
• The group was led by local samurai from various parts of Mutsu Province who were renowned for their military prowess; there were six of them

It includes the following:

Another notable aspect is that , in addition to intelligence gathering and covert operations, they were also responsible for logistics, such as transporting weapons and provisions

If that were true, it could be interpreted as a supply unit composed of ninjas, and regardless of its veracity, it is a very interesting topic

In Japanese history, supply units have often been somewhat undervalued, but in reality, they play a crucial role that can make or break any operational effort

It is easy to imagine that, especially in those times when transportation routes were likely not well-developed, supplying goods across dangerous areas that would include combat zones required a high level of operational capability

In that respect, it could be argued that ninjas, a specialized group skilled in controlling intelligence networks, were well-suited to serve as a supply unit

As mentioned earlier, the author and date of composition of "Rojin Denmonki" are unknown, but there is a paper (Yukiyoshi Hotta, "Basic Research on Samurai Status in the Sendai Domain," Miyagi University of Education Bulletin, Vol. 51, Miyagi University of Education, 2017　https://mue.repo.nii.ac.jp/records/536 ) that mentions the possibility that it was written in the 19th century by a "Daibanshi," a middle-ranking samurai of the Sendai Domain.

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The Date family's "ninja" as seen in the "Masamune Chronicle"

On the other hand, there are reliable documents from Masamune's time that seem to mention the existence of "ninja."

This is the "Masamune-ki," written by Date Shigezane, a senior retainer of Masamune .

This is a biographical account that comprehensively covers events from 1584, when Masamune became the head of the Date clan, until his death in 1636, encompassing not only military actions but also his daily life and hobbies

Because Shigemitsu himself was a warrior who participated in battles and wrote based on his firsthand experiences from a position very close to Masamune, "Masamune-ki" is considered a document of high historical value

There is a part in that description that uses the word "grass"

This is a military term from the Oshu region meaning "stealth" or "covert operations," and is therefore part of a reference to ninjas

There, the roles of the grass are described as including actions such as "preparing," "entering," "lying down," "raising," and "searching."

"Chōgi"refers to devising strategies or attacking the enemy,"Iru"means to infiltrate the enemy's territory, and"Ga"means to lie low.

Furthermore,"to raise"means to eliminate enemy spies,"to search"means to search for enemy spies hiding in one's own territory.

The fact that there were ninjas referred to by the cryptic, coded term "kusa" (草) is recorded in primary historical sources and is therefore a significant finding

Therefore, regardless of whether the "Kurohabaki-gumi" mentioned in later documents actually existed, it is highly probable that Masamune did employ a group of ninjas

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