Sanada Masayuki

Portrait of Sanada Masayuki

Sanada Masayuki (1547—July 13, 1611) was a damiyō who controlled Ueda Castle in Shinano Province and is famous for being the father of Sanada Nobuyuki and Sanada Yukimura. He started out being a vassal to the Takeda, however, after the clan fell in 1582, he managed to work his way through several temporary alliances to gain a domain all his own within territory that used to be a part of the Takeda. Sanada Masayuki is considered to be one of the greatest military strategists of the Sengoku Jidai.

Masayuki was born in 1547 and was known as Gengorō.(1) Since he was Sanada Yukitaka’s third son, he would not be the one to succeed his father, but fate would have different plans.

At the age of seven, Masayuki was sent to the Takeda clan’s headquarters as a hostage, where he became part of Takeda Shingen’s Okukinjūshū, a group of six young servants who were close to him.(2) Most sources do not state it directly, but it is possible that Shingen had a homosexual relationship with these boys, especially Masayuki, since he was favored by the warlord for he recognized that Masayuki could easily rival his father when it came to his talents and insight.(3) However, no sources state this explicitly, so I am only speculating, but considering Shingen’s history, it is a possibility.(4) It is because of Masayuki’s talents that he is sometimes included in the famous Twenty-Four Generals of the Takeda, among them were his father and two elder brothers.

During the 1560s, Masayuki became more active within the Takeda clan, fighting in famous battles such as the Fourth Battle of Kawanakajima in 1564 and the Battle of Mimasetōge in 1569.(5) In 1564, he married Yamanote-dono, who gave birth to Sanada Nobuyuki in 1566 and Sanada Yukimura in 1567. Things began to change after the Battle of Mikatagahara in 1573, a battle that Masayuki also participated in.(6)

In May 1573, Takeda Shingen died, turning the clan over to his son, Takeda Katsuyori, who infamously led the clan into ruin, starting with the Battle of Nagashino in 1575. Before this battle, in 1574, Sanada Yukitaka died, making Masayuki’s eldest brother, Sanada Nobutsuna head of the clan. That title would soon fall to Masayuki, as both Sanada Nobutsuna and Sanada Masateru were among the many that were killed at Nagashino.(7)

A couple of years after the death of Uesugi Kenshin and the formation of an alliance between the once rival clans, Takeda Katsuyori ordered Masayuki to invade western Kōzuke, which was under the control of the Hōjō clan, and seized Numata Castle.(8) In 1581, he was in charge of supervising the construction of Shinpu Castle at Nirasaki, however, he also had to deal with Numata Kageyoshi, the former lord of Numata Castle who was trying to retake his old lands. This was handled promptly with a planned assassination, preventing him from recapturing Numata Castle.(9) Since I cannot find any information regarding Numata Kageyoshi, I cannot confirm if he was assassinated or just simply abandoned the plan.

In April 1582, the Oda-Tokugawa alliance began invading Kai to finish off the last of the Takeda clan. Masayuki tried to convince Katsuyori to abandon Kai and come to Iwabitsu Castle in Kōzuke, but Katsuyori sought shelter with Oyamada Nobushige at Iwadono Castle. Unfortunately, Katsuyori was betrayed, and he died at Tenmokuzan. The fall of the Takeda clan resulted in Masayuki yielding to Oda Nobunaga, who placed him under Takigawa Kazumasu. He was able to keep most of his domains, however, Masayuki would have to abandon Numata Castle.(10) The Sanada did not serve the Oda long, for Nobunaga was betrayed by Akechi Mitsuhide and died in June 1582.

Nobunaga’s assassination caused a panic throughout the Oda allies, and the Uesugi, Hōjō and Tokugawa saw this as an opportunity to gain the lands that were previously under the Takeda. On July 5, 1582, Takigawa Kazumasu was forced out of the region by the Hōjō. During this battle, Masayuki escorted Kazumasu’s forces though Suwa in Shinano Province, but sent his uncle, Yazawa Yoritsuna, to take Numata Castle back for the Sanada. He also sent his eldest son, Nobuyuki, to be in charge of Iwabitsu Castle.(11)

On July 10, 1582, the Uesugi decided to invade northern Shinano, and originally, Masayuki had sided with them, but he later defected and sided with the Hōjō clan. The Uesugi and Hōjō were about to face off at Kawanakajima, but the Hōjō found themselves invading Kai Province after the Tokugawa did the same thing. The Hōjō almost conquered Shinano, but Masayuki defected once again in October 1582, siding with the Tokugawa, which ended with the two clans forming an alliance. The following year, Masayuki began construction of Ueda Castle.(12)

Problems arose once again after Ieyasu surrendered to Toyotomi Hideyoshi in 1584. Hōjō Ujinao began pressing Ieyasu about returning Numata Castle to the Hōjō clan, a castle that was now part of the Sanada domain. When Masayuki was asked to hand over the castle, he refused, for this was a castle that was hard won by the men of the Sanada. This led to the First Siege of Ueda Castle in 1585, which resulted in a victory for the Sanada clan, and they now were vassals to the Toyotomi. As part of the peace negotiations between the two clans, Masayuki married off his eldest son, Nobuyuki, to Komatsu-dono, the daughter of Honda Tadakatsu and adopted daughter of Ieyasu.(13) This did not stop the Tokugawa and the Hōjō from trying again, for in 1586, the Hōjō tried for Numata again but was repelled and the Tokugawa tried for Ueda again, but Hideyoshi intervened. The Hōjō would continue to try for the next several years, however, this war making went against a law Hideyoshi had put into place that prohibited daimyō from engaging in battles over personal disputes, which ultimately led to the Odawara Campaign in 1590.(14) Masayuki fought alongside Maeda Toshiie and Uesugi Kagekatsu as they made their way through the Usui Pass, being present for the slaughter at Hachiōji Castle.

From what I could find, it does not seem that the Sanada clan partook in either of the invasions of Korea, and Masayuki does not appear in history books again until after the death of Hideyoshi in 1598, leading up to Sekigahara. There is much speculation about why the clan ended up being divided during this time, for Masayuki and Yukimura sided with the Western Army while Nobuyuki sided with the Eastern. Many historians claim that Masayuki ordered his sons to join opposing sides, allowing for the Sanada to survive the conflict, regardless of which side won. This is a serious gamble, for that means that both Nobuyuki and Yukimura had to survive the conflict. On top of this, I cannot help but mention that both brothers sided with their wives’ families. Regardless of the reason, the clan ended up splitting before the Battle at Sekigahara, with father against son, and brother against brother.

While they were not at Sekigahara proper, Masayuki played a major role in the campaign as a whole, and had it not been for the devastating betrayal of Kobayakawa Hideaki, it could have resulted in a defeat for Ieyasu. Tokugawa Hidetada, instead of leading his forces directly to Sekigahara, made a detour to Ueda Castle, and on October 12, 1600, began the Sceond Siege of Ueda Castle. Since the castle did not fall as quickly as he hoped, Hidetada abandoned the siege on October 16, 1600, making him arrive late for the main event. While this was a victory for the Sanada in the Western Army, it was short lived, for Ishida Mitsunari was defeated on October 21, 1600.

In January 1601, Sanada Masayuki and Sanada Yukimura were sent into exile at Kudoyama, only being spared death due to Sanada Nobuyuki’s service during the campaign. He would die of illness ten years later, still in exile. While only a small domain daimyō, Sanada Masayuki managed to make a reputation for himself and his clan, and while Hideyoshi claimed, “that his allegiance was fickle and not to be trusted”, Masayuki has been celebrated, rather than vilified since the Edo period.(15)


  1. “Sanada Masayuki”,, last accessed 7/9/2022
  2. “Sanada Masayuki”,, last accessed 7/9/2022
  3. “Sanada Masayuki”,, last accessed 7/9/2022
  4. “A Samurai Who Wrote Love Letters to Boys”, Let’s ask Shogo | Your Japanese Friend in Kyoto, YouTube Shorts., last accessed 7/9/2022
  5. “Sanada Masayuki”,, last accessed 7/9/2022
  6. “Sanada Masayuki”,, last accessed 7/9/2022
  7. “Sanada Masayuki”,, last accessed 7/9/2022
  8. “Sanada Masayuki”,, last accessed 7/9/2022
  9. “Sanada Masayuki”,, last accessed 7/9/2022
  10. “Sanada Masayuki”,, last accessed 7/9/2022
  11. “Sanada Masayuki”,, last accessed 7/9/2022
  12. Chaplin, Danny. Sengoku Jidai: Nobunaga, Hideyoshi, and Ieyasu: Three Unifiers of Japan (2018), p. 340
  13. Chaplin, Danny. Sengoku Jidai: Nobunaga, Hideyoshi, and Ieyasu: Three Unifiers of Japan (2018), p. 340
  14. “Sanada Masayuki”,, last accessed 7/9/2022
  15. “Sanada Masayuki”,, last accessed 7/9/2022