Shima Sakon

Woodblock painting of Shima Sakon

Shima Sakon (June 9, 1540-October 21, 1600?) is most famous for being a strategist serving under Ishida Mitsunari and was present at the Battle of Sekigahara, His life is a bit of a mystery, especially since he spent most of his life as a rōnin. He was born in Yamato Province and lived in the city of Heguri.(1) He first served the Hatakeyama clan of Yamato, fighting alongside them at the Battle of Kyōkōji against the Miyoshi clan. This ended in defeat for the Hatakeyama clan, forcing Sakon to flee. He joined the Tsutusi clan, who took over Yamato. He first served Tsutsui Junsho before serving his son, Tsutsui Junkei until he died in 1584. He became a landowner under the Tsutsui clan, and under Junkei, he led a war against Matsunaga Hisahide, who was trying to take over Yamato Province.(2) This is the version of Sakon’s life that most historians claim as truth. It was under the Tsutsui clan where he received the name of “Sakon” or “right hand”. One unverified source states that Shima Sakon served under Takeda Shingen for a time, however, since it cannot be verified, it is not accepted as part of his narrative.(3)

After the death of Tsutsui Junkei, Sakon joined the Toyotomi clan, serving under Toyotomi Hideyoshi’s brother, Hidenaga. He joined before the Kyūshū Campaign of 1586 to which he participated in. Sakon stayed with the Toyotomi until Hidenaga’s death, and once again, Shima Sakon was a rōnin.(4)

For a time, Sakon was pursued by many clans, offering rewards for joining them. Sakon turned down many offers, however, he accepted the offer from Ishida Mitsunari after he made a second offer, paying him three times his personal salary: 20,000 koku. This is the accepted story but some claim that he only worked for Mitsunari after he became the ruler of Sawayama Castle and had an income of 190,000 koku.(5)

After Toyotomi Hideyoshi died in 1598, a division formed within the Toyotomi clan. Mitsunari supported Hideyori, Hideyoshi’s son, while Tokugawa Ieyasu looked for a way to take over. Though most historians doubt this, Sakon did come up with a plan to eliminate Ieyasu. He proposed the idea to Mitsunari, but he did not approve of the plan. Sakon tried for the plan anyway. He was joined by Natsuka Masaie, who was the lord of Minakuchi Castle in Ōmi Province. They invited Ieyasu to the castle, and the plan was to assassinate him there, however, Ieyasu canceled the visit after his spies discovered the plan.(6)

Before the Battle of Sekigahara, Sakon took 500 soldiers and fought a small battle against the Eastern Army stronghold at the Battle of Kusegawa. It was won by the Western Army. The night before Sekigahara, two different sources have two different stances on the events revolving around a plan for a surprise attack at night. It is unclear if Sakon supported the surprise attack that was brought up by veteran samurai, Shimazu Yoshihiro.(7)

The end of Shima Sakon’s life is not exactly clear. The most common end to Sakon’s life is at the Battle of Sekigahara. After the betrayal of Kobayakawa Hideaki, the battle took a turn for the worst for the Western Army. Sakon attacked the Eastern Army head-on, along with his two sons, and were killed by arquebus fire. This is questionable though, for his body was never found on the battlefield afterwards.(8)

The other theory is that he managed to escape Sekigahara, but died from his wounds a month later. While there is a lack of hard evidence, oral traditions state that Sakon was spotted multiple times around Kyōto and his gravestone states that he survived Sekigahara and died in 1632.(9)


  1. “Shima Sakon”., last visited 8/19/2021
  2. “Shima Kiyooki”., last visited and translated 8/19/2021
  3. “Sakon Shima”., last visited 8/19/2021
  4. “Sakon Shima”., last visited 8/19/2021
  5. “Shima Kiyooki”., last visited and translated 8/19/2021
  6. “Shima Kiyooki”., last visited and translated 8/19/2021
  7. “Shima Kiyooki”., last visited and translated 8/19/2021
  8. “Shima Sakon”., last visited 8/19/2021
  9. “Sakon Shima”., last visited 8/19/2021