was the eldest son of Matsudaira Ieyasu. His ''tsūshō'' ("common name") was . He was called also , because he had become the lord of in 1570. Because he was a son of Tokugawa Ieyasu, he is often referred to, retroactively, as .

Biography

Nobuyasu was Ieyasu's first son. His mother was

Lady Tsukiyama Lady Tsukiyama or (d. 9 September 1579) was a Japanese noble lady and aristocrat from the Sengoku period. She was the chief consort of Tokugawa Ieyasu, the ''daimyō'' who would become the founder and first ''shōgun'' of the Tokugawa shogunat ...

, daughter of Imagawa Yoshimoto. His childhood name was Takechiyo (竹千代). As a child Nobuyasu was sent to the Imagawa capital of Sunpu, located in

Suruga Province was an old province in the area that is today the central part of Shizuoka Prefecture. Suruga bordered on Izu, Kai, Sagami, Shinano, and Tōtōmi provinces; and was bordered by the Pacific Ocean through Suruga Bay to the south. Its abbrev ...

(modern-day

Shizuoka Prefecture is a prefecture of Japan located in the Chūbu region of Honshu. Shizuoka Prefecture has a population of 3,637,998 and has a geographic area of . Shizuoka Prefecture borders Kanagawa Prefecture to the east, Yamanashi Prefecture to the northea ...

) as a hostage. Later he was named keeper of

Okazaki Castle is a Japanese castle located in Okazaki, Aichi Prefecture, Japan. At the end of the Edo period, Okazaki Castle was home to the Honda clan, ''daimyō'' of Okazaki Domain, but the castle is better known for its association with Tokugawa Ieyasu an ...

in Mikawa Province (modern-day

Aichi Prefecture is a prefecture of Japan located in the Chūbu region of Honshū. Aichi Prefecture has a population of 7,552,873 () and a geographic area of with a population density of . Aichi Prefecture borders Mie Prefecture to the west, Gifu Prefecture ...

), the birthplace of his father, and took part in the

Battle of Nagashino The took place in 1575 near Nagashino Castle on the plain of Shitaragahara in the Mikawa Province of Japan. Takeda Katsuyori attacked the castle when Okudaira Sadamasa rejoined the Tokugawa, and when his original plot with Oga Yashiro for t ...

in 1575. It is generally believed that Nobuyasu's mother and his wife, the Lady Tokuhime, daughter of

Oda Nobunaga was a Japanese ''daimyō'' and one of the leading figures of the Sengoku period. He is regarded as the first "Great Unifier" of Japan. Nobunaga was head of the very powerful Oda clan, and launched a war against other ''daimyō'' to unify ...

, did not get along. It's possible that Lady Tsukiyama was jealous of the attention her son paid to his young wife. In 1579, whether out of a desire for revenge or to remove her mother-in-law's meddling in their marriage, Tokuhime wrote a letter to her father

, accusing her mother-in-law of a treasonous plot with the

Takeda clan The was a Japanese samurai clan active from the late Heian period until the late 16th century. The clan was historically based in Kai Province in present-day Yamanashi Prefecture. The clan reached its greatest influence under the rule of Taked ...

. When Nobunaga brought the allegations to the attention of Ieyasu, he had his wife confined and then executed, to allay any suspicions of his ally. Nobuyasu was confined to Ohama and then Futamata Castle, where he received his father's order to commit suicide (''

seppuku , sometimes referred to as hara-kiri (, , a native Japanese kun reading), is a form of Japanese ritual suicide by disembowelment. It was originally reserved for samurai in their code of honour but was also practised by other Japanese people ...

''), in a letter which stated that Ieyasu understood that Nobuyasu may not have been guilty of any treasonous act, or even knew anything about it, but he understood that Nobuyasu would feel obligated to avenge his mother. The possibility of revenge was an unacceptable risk to Ieyasu, and the only solution was that Nobuyasu should kill himself for the integrity and security of the clan. Nobuyasu committed seppuku and killed himself on 5 October 1579, or the 15th day of the 9th month, of the year Tenshō-9, by the traditional Japanese calendar. Nobuyasu is not believed to have been a popular figure in his time, as his demise might attest. In particular, supposedly Sakai Tadatsugu declined to refute any suspicions of treason, due to his personal disregard for Nobuyasu.

Issue

* Toku-hime, who married Ogasawara Hidemasa of Matsumoto Domain * Kumahime, who married

Honda Tadamasa was a Japanese ''daimyō'' of the early Edo period, who ruled the Kuwana Domain and then the Himeji Domain. He was the son of Honda Tadakatsu. Tadamasa's first battle was during the Siege of Odawara, in 1590; he also fought at the Battle of S ...

* Banchiyo, who was the son of a concubine

References

*Griffis, William (1883). ''The Mikado's Empire,'' Book I. New York: Harper & Brothers, p. 272 1559 births 1579 deaths Tokugawa clan Suicides by seppuku Deified Japanese people {{Japan-noble-stub