During a research project a while ago, I came across an interesting point regarding Tokugawa Ieyasu, the feudal lord to unify all of Japan in the early 1600s, and first shogun of the Tokugawa Bakufu (徳川幕府, Militaristic rule of the Tokugawa clan). I came across notes online that state he would have himself addressed as “Tokugawa Minamoto Ieyasu” (徳川源家康) within some administrative-related letters and documents¹. For those who are familiar with the earlier years of Japanese history should know about the Minamoto clan, which was a powerful clan with nobility roots to the Imperial family, and greatly recognized for their prowess in military campaigns by a few exemplary individuals from the Heian period to the Kamakura period. What is this significant link that the Tokugawa family have with this clan?

Before modern Japan, it was commonplace for people to change their names. There are numerous reasons for this, such as to represent one’s (new) living area, job title, adoption into a new family, rise in status, and so on². In most cases, an explanation is given in surviving documents, whether it be in the form of a diary, family records, of official papers. In some of these cases, however, are critical disputes on the validity of these documents and their claims.

For this article, we will look at Tokugawa Ieyasu and the story behind the lineage he established. This ranges from his own personal history, the factors in which prompted him to take on a new name, as well as his family line’s connection to the Minamoto clan. Some of the sources used for this includes the following:

• Tokugawa World (Buke no Kamon no Yurai)
• Mikawa Komachi
• Umakomi to Ota-ku no Rekishi wo Hozon suru Kai
• Tokugawa Ieyasu no Genji Kaimei Mondai / 徳川家康の源氏改姓問題
• Tokugawa Ieyasu Kou

GENJI – MATSUDAIRA STORY

Ieyasu was born in the Matsudaira family, who were from Matsudaira Village in Kamo District of Mikawa Province (present day Matsudaira Town, Aichi Prefecture). The Matsudaira family were an influential one, who would eventually gain full control over their domain for many years once there was no one to challenge them. After becoming shogun and establishing the Tokugawa Bakufu in the early 1600s, Ieyasu presented a genealogy for his family line, which illustrates the Matsudaira line was started by Matsudaira Chikauji (松平親氏). This Matsudaira Chikauji is stated to have a link to the Seiwa-Genji lineage (清和源氏), which is but one of the different lines that have ancestry to the noble Genji clan.

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Some points to understand regarding this Seiwa-Genji line:

• This line descends from the 56th successor Emperor Seiwa, making it the most powerful of all the other Genji lines.
• All Genji lines originate from the Minamoto clan, a family of nobility whom were once one of many imperial families during the Heian period.
• While they have a long history, the Minamoto clan are especially renown for their on-going struggle for power against the Taira clan which eventually lead to victory within the late Heian period (794-1185).
• One of the main representatives of this Seiwa-Genji line is Minamoto no Yoshiie (源義家, 1039-1106), who is viewed as a legendary figure being the role model for the brave, armor-clad warriors whom would later rise and establish Japan into a military state.

Here’s an explanation of Tokugawa Ieyasu’s claim to the Seiwa-Genji link. His ancestor, Chikauji, is a descendant of the Serata³ clan, which split from the Nitta-Genji (新田源氏) line (another branching line from the original Seiwa-Genji). The Serata clan left the Nitta Manor in Tokugawa Village (新田庄徳河郷), and later established their own home in Serata Village in another part of Tokugawa (世良田郷徳河) within Ueno Province⁴. According to different sources, early in the Muromachi period (1336-1573), Chikauji and his father Arichika (有親) fought alongside with others against the Kamakura bakufu within the Shinano area in eastern Japan. They were on the losing side, and had to flee from the pursuit of Ashikaga Takauji and his force. Not being able to return to their homeland, they escaped to Sagami Province. Reaching the Shōjōkō Temple, Chikauji took vows there to become a Jishu sect monk under the name “Tokuami” (徳阿弥)⁵. Later, he would travel to Matsudaira Village in Mikawa, and became a member of the Matsudaira family through marrying the daughter of Matsudaira Taro Saemon. Thus, Ieyasu’s claim is that his blood line directly comes from Minamoto no Yoshiie through Chikauji, as well as past generations were known as “Tokugawa” due to Serata Village being in Tokugawa.

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Above is a genealogy chart I’ve prepared that illustrates the generations that progresses from Minamoto no Yoshiie all the way to Matsudaira Chikauji. It also includes how certain individuals changed their surname generally based on the geographical location they were living in, which led to the establishment of new branching family lines. Some of them even did this multiple times. If we look at Chikauji at the bottom of the 2nd image, he too is a prime example of switching surnames. Apparently he went by “Tokugawa” at one point when he was residing at Tokugawa Village, while he would eventually switch to Matsudaira.

IEYASU AND HIS CHANGE TO TOKUGAWA

Looking into Tokugawa Ieyasu’s personal history, he went through a period where his identity changed in stages before establishing the Tokugawa shogunate and ruling all of Japan. As a summary, he was known by the name of Takechiyo (竹千代) during his childhood. When he was given his ceremony of adulthood at the age of 16⁶, his given name 1st changed to Motonobu (元信), then later to Motoyasu (元康) while working under Imagawa Yoshimoto, but kept his family name “Matsudaira” the same. He inherited the role of the 9th head of the Matsudaira clan, yet didn’t spend much of his life with them in Mikawa after the age of 6, for he was sent away as a hostage⁷ by his father, Matsudaira Hirotada. He was 1st under the care of Oda Nobuhide in Owari Province for 2 years, then later sent to his intended caretaker Imagawa Yoshimoto in Suraga Province, who lorded over Mikawa. Eventually, he would gain complete control over Mikawa when Yoshimoto died during the battle of Okehazama in 1560, which was the final of the ongoing war this individual had against the ambitious warlord Oda Nobunaga. His military career truly took off under the title of Matsudaira Motoyasu, and would continue especially after his identity undergone yet another change.

In 1563 he would alter his first name, from “Motoyasu” to “Ieyasu”. 3 years later, he would then change his family name from “Motoyasu” to “Tokugawa” as an official title from the Imperial court. While it is very common to have one’s family name changed in relations to receiving an official rank with some sort of back story, there is none whatsoever in Ieyasu’s case at the time. It would be many years later during the 1st year of the Edo period that Ieyasu would reveal that in his family’s genealogy, which traces back to the Serata clan, there were a few individuals who bore the name Tokugawa. It is through this connection that he believed it was best to reinstate this name. Some researchers question this as there was no mention of this in his earlier years, especially from someone who grew up away from his own clan members during his youth. Another interesting point that is mentioned is that members of Ieyasu’s Matsudaira clan did not change their family name to Tokugawa after his rise in power, but did not hesitate to use this surname when needed.

QUESTIONING THE AUTHORITY TO POWER

By setting up the new Tokugawa bakufu in Edo (present day Tokyo), Tokugawa Ieyasu was able to establish rules, regulations, and territorial development process throughout Japan. Official documentations were also transcribed, which were used to retain all sorts of important information. Some examples of these are the Mikawa Monogatari (三河物語), which is a documentation of historical tales and accomplishments regarding families from Mikawa including the Matsudaira/Tokugawa, and the Kansei Chōshū Shokafu (寛政重脩諸家譜), which is a collection of many different genealogy, including that of land owners and military families. In these we can see the genealogy of Ieyasu, which claims an ancestral link to the Minamoto clan through the Seiwa-Genji line.

Despite these documentations, historians and researchers are skeptical about this claim. Some of these arguing points include the following:

• There is very little concrete info on those individuals who come before Chikauji
• There is no evidence of a Serata member migrating to Mikawa, let alone it being Chikauji
• Outside of Ieyasu’s genealogy claim, there are no other details regarding a family lineage presented by other Matsudaira members

There isn’t much solid proof of where such a well-detailed genealogy comes from. Taking his historical account into consideration, Ieyasu didn’t spend a lot of his time in Mikawa, let alone amongst his Matsudaira clan members. This isn’t an unusual case, to be honest. There are even some questions regarding those that come after Chikauji in this genealogy, but for this article I will refrain from discussing those, as they don’t have the same weight as the ones mentioned above. What’s interesting to note is that Imagawa Yoshimoto, Ieyasu’s primary care taker in his early years, also claimed a link to the Seiwa-Genji lineage. Possibly this is where Ieyasu got the idea from and decided to follow suit?

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If there is solid ground for skepticism, what would be the benefit of fabricating a lineage? Understand that after military rule was established by Minamoto no Yoritomo as the 1st ruling Shogun during early Kamakura period (1185 ~ 1333), not just anyone could simply use force and claim the title as “shogun”. It had to be acquired through the following 2 points:

1) Appointed by the Emperor

2) It could only be given to those of (according to very old beliefs and fables) “noble families that were descendants of the gods that created Japan and the world”

While we will not delve into the specifics of the 2nd point, we can sum this point up by the fact that the Minamoto clan, like many other noble families, was established with the proclamation of ancestry under a specific god, thus their connection with the Imperial court bearing the status of nobility. This link to nobility, along with other factors, is what granted Minamoto no Yoshiie the qualification to be appointed as shogun by the Emperor during his military career⁸. It is not hard to see the advantage of claiming rights to rule as Shogun through a link to the Seiwa-Genji lineage.

Claims to nobility wasn’t something that only Ieyasu took advantage of, for there were others before him who used the same proclamation to acquire the shogun title. For example, the Ashikaga clan, whom had a long line of shogun successors throughout the Muromachi period (1336 ~ 1573), also did the same and claimed ancestry to the Seiwa-Genji lineage. Toyotomi Hideyoshi also dabbled in such play of claiming a link to nobility, for when he was able to rise to the top through superior military strength over his adversaries, he was initially faced with an issue that would prevent him from becoming shogun. The son of a lower class family, Hideyoshi was not born with a noble surname, meaning he had the blood of a mere commoner. To rectify this situation, he was advised, as well as permitted, to be adopted by an Imperial court noble named Konoe Sakihisa. Through this newly-established noble link, Hideyoshi was allowed to receive the title shogun from the Imperial court.

CONCLUSION

This research on Tokugawa Ieyasu’s claimed genealogy, along with the critical disputes against it is an interesting one. It gives a glimpse of methods those who have the means can use in order to secure their position to achieve success or claim power. Even though this matter is centuries old, researchers still take the time to examine just how real the roots of the unifier of Japan truly is in order to understand the history of his ancestors…that is if any traces of it can be discovered. It’s but one of the many ways to learn about the past and understand Japan when society was structured very differently from modern times.

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1) In a related topic, the online edition of Sankei News reported about a letter written in 1586, where Tokugawa Ieyasu used the title addressed as “Fujiwara Ieyasu” (藤原家康) in 1586. It appears that along with the surname change to “Tokugawa”, Ieyasu initially wanted to elevate his status even higher through an ancestral link to the Fujiwara family. For those unfamiliar with this, the Fujiwara family were elite to the point that they were not only the most influential in the Imperial court, but they also had control of the Imperial house behind the scenes through manipulating which member of the Imperial family would be the next successor. Toyotomi Hideyoshi, Ieyasu’s predecessor, was another who used the Fujiwara surname at times after he established himself with a noble lineage.

You can see the actual news report here.

2) One of the more interesting cases I’ve heard is that some people would change both their given and family names if they feel their current ones are unlucky. To improve their luck, changing them to ones that are more appealing in meaning is a route that is seen as beneficial.

3) Also pronounced as “Serada”

4) The kanji (Chinese-bsed characters) for “Tokugawa” uses an older way of writing. There are different ways in which this name has been written throughout the ages. Here are the following:

• 徳川 (most familiar)
• 徳河
• 德川
• 得川
• 禿川
• 禿河

5) This is explained in the “Mikawa Monogatari” (三河物語). There is a slightly different take on this in an earlier publication called “Matsudaira Yuishogaki” (松平氏由緒書). This too presents descriptions regarding the Matsudaira genealogy, but for Chikauji’s case he is not written to have been a monk. Instead, he left his hometown on a solo journey across the lands like a wanderer. Because of this, there are beliefs that this part about him becoming a monk is a fabrication, and added to later documentations.

6) This is known as “genpuku” (元服) in Japanese.

7) This “hostage” case is very common throughout Japan’s history. Different from the idea of kidnapping by force, in many situations a clan that is controlled by another more powerful clan would send family members to reside with them. While these members are given to fulfill a particular need by the powerful clan, the gist of it is to keep those family members in order to control the lesser clan. There are also many political usages behind this.

8) Before the establishment of military rule, the title “shogun” had a slightly different nuance, along with a different manner of entitlement. During the Nara and Heian period, certain renown warriors who were recruited to deal with supposed threats (i.e. “barbarians” and “villains”) to the Imperial palace and the aristocratic governing system would be given this title. In Minamoto no Yoshiie’s case, his complete title was “Chinjufu Shogun” (鎮守府将軍), which has the full meaning of “Commander-in-Chief of the army which pacifies threats from the North”.