Lifespan: Tenbun 10 (1541) (?) to 3/9 of Keichō 4 (1599)
Other Names: Tadakane, Kōkan, [Common] Genta, Kamon-no-suke, Uemon-no-taifu
Lord: Shimazu Yoshihisa
Father: Ijūin Tadaao
Siblings: Tadamune, Harushige
Wife: Daughter of Shimazu Hisasada
Children: Tadazane, Kodenji, Kimotsuki Kanehiro, Senji
Ijūin Tadamune served as a bushō during the Sengoku and Azuchi-Momoyama periods. He was a retainer of the Shimazu clan of Satsuma Province.
Tadamune was born as the son of Ijūin Tadaao, a chief retainer of the Shimazu. He was originally called Tadakane and, by 1576, changed his name to Tadamune.
From early on, Tadamune served Shimazu Yoshihisa, becoming the head of the chief retainers and managing political affairs for the Shimazu clan. As a bushō, he deployed to Higo and Chikuzen provinces and made significant contributions on the battlefield. Tadamune also excelled in tanka, maintaining friendly relations with Hosokawa Fujitaka. Beginning prior to the Subjugation of Kyūshū by Toyotomi Hideyoshi, he engaged in peace negotiations with the Toyotomi.
In 1587, when confronted with the massive Toyotomi army led by Hideyoshi and a gradual weakening of the Shimazu army relative to the Toyotomi, Shimazu Yoshihisa and his son, Shimazu Yoshihiro, asserted that the clan should resist, while Tadamune recommended their surrender. Nevertheless, the Shimazu continued to fight against Hideyoshi’s forces. On 4/17 of Tenshō 15 (1587), Yoshihisa and Yoshihiro led 20,000 elite forces to attack the base of Toyotomi Hidenaga. This is known as the Battle of Nejirozaka. Upon a signal that the left division led by Hongō Tokihisa would charge the enemy, Tadamune was supposed to advance with the right division, but, perhaps because Tadamune did not hear the signal, his division did not advance at all. As a result, many soldiers in the left division were killed and the Shimazu army was forced to withdraw in defeat. After the battle, Tadamune underwent the rites of tonsure and surrendered himself as a hostage to Hideyoshi. To plead for forgiveness from the Shimazu family, he aimed to persuade Yoshihisa and others. Under one theory, his explanations enabled the Shimazu clan to continue to exist.
Hideyoshi was impressed by the abilities demonstrated by Tadamune and, after the Subjugation of Kyūshū, directly awarded him the Kimotsuki District in Ōsumi Province. Thereafter, as a chief retainer of the Shimazu clan, he frequently engaged in direct negotiations with the Toyotomi administration, cultivating close relationships with magistrates including Ishida Mitsunari. In 1595, the Toyotomi administration conducted a land survey in the territory of the Shimazu and, in place of the Hongō clan, he was granted landholdings of 80,000 koku in Shōnai in the Morokata District of Hyūga. Meanwhile, the Hongō were transferred to Kedōin with a smaller fief. After completion of the survey, Tadamune was further given responsibility for managing the reallocation of lands within the Shimazu clan, making him a target of the dissatisfaction of members of the Shimazu clan. Thereafter, he proudly wielded authority, drawing the vigilance of members of the main branch of the Shimazu family.
On 3/9 of Keichō 4 (1599), Tadamune was slayed with a sword by Shimazu Tadatsune, the son of Shimazu Yoshihiro, at the Shimazu residence in Fushimi. Tadamune’s wife made a direct appeal to Tokugawa Ieyasu over a period of three days, but Ieyasu ignored her appeal on the basis that he could not understand the Satsuma dialect spoken by Tadamune’s wife. A monk at the Fugen Temple in Rakuhoku sent a letter to the retainers of Shimazu Yoshihiro noting that Tadamune’s wife and children were requesting everywhere for prayers for the dispersal of their mortal enemy (Tadatsune) so they should be vigilant of his surroundings.
Reasons for his slaying
In military chronicles of Shōnai, Tadamune aspired to become the military governor of Satsuma, Ōsumi, and Hyūga provinces and revealed to Ishida Mitsunari a plot to poison to death Tadatsune. After hearing of these plans from behind sliding doors, Tadatsune proceeded to kill him. In an alternate version of events, Tadamune revealed his plans to Tokugawa Ieyasu, but neither account is backed by contemporaneous sources. Based on recent research, theories are posed that the killing was connected to problems within the Shimazu family. According to one account, Tadatsune plotted the murder on his own while, in another, he conspired with Yoshihiro and obtained consent from Yoshihisa. After the incident, Ishida Mitsunari sent a letter of reprimand to the Shimazu family to which Yoshihisa replied that the act was committed by Tadatsune on his own.
Tadamune’s political position was comparable to Yoshihiro, and, after the killing, the fact that Yoshihisa quickly responded to Tadazane suggests that Yoshihisa may have been involved in the plot. Alternatively, while the act may have been related to political tensions in the Shimazu family, Yoshihiro and Tadatsune may have conspired together. Or, as stated by Yoshihisa, the killing may have been the result of Tadatsune’s personal animosity toward Tadamune.
View from the Shimazu family
In the personnel records of the Satsuma domain, Tadamune is not identified as a retainer, but, rather, as a traitor. Records related to the Shimazu family state that “Tadamune embraced independence and harmed his lord.” Moreover, it is noted that he planned to surrender early to Hideyoshi and, at the Battle of Nejirozaka, only pretended to engage in battle but did not actually do so.
In his own accounts, Shimazu Yoshihiro noted that, at the Battle of Mimikawa, Tadamune was impatient to earn recognition, so he violated an order not to traverse the river. After several battalions crossed, many troops died as a result. This account, however, is not substantiated in any other sources. Moreover, Tadamune and members of the Ijūin family are not identified among those who crossed, nor are there traces of any punishment of Tadamune.
Most of the information regarding Tadamune is contained in records of the Shimazu family and the military chronicles written in the Edo period. Owing to the end of the Ijūin family, Tadamune was not the subject of further evaluation in the latter part of the Edo period.
Character and Anecdotes
Tadamune was an ardent follower of the Ikkō sect (an offshoot of the Jōdo sect) and appeared to have made many donations. Once, when Tadamune and his wife visited the Ishiyama-Hongan Temple, he desired a wooden statue of Shinran, the founder of the Jōdo sect in the early Kamakura period. There was a rule at the temple not to transfer items so the hosts politely refused his request, whereupon Tadamune became enraged, saying this was a dishonor for a bushi, and drew his sword, threatening the hosts. The temple then hurriedly gave him a wooden statue that was said to have been made by Shinran himself.
Although regarded as a traitor in the Shimazu family, an account written in the middle Edo periods notes that he was a loyal person who saved the Shimazu family from being extinguished after the Subjugation of Kyūshū by Toyotomi Hideyoshi.