Lifespan: Tenbun 13 (1544) to 10/8 of Tenshō 13 (1585)
Rank: bushō; sengoku daimyō
Titles: Junior Fourth Rank (Lower); Master of the Eastern Capital Office
Father: Date Harumune
Mother: Kubohime (daughter of Iwaki Shigetaka)
Siblings: Iwaki Chikataka, Onamihime, Terumune, Shōseiin (wife of Date Sanemoto), sister (wife of Koyanagawa Morimune), Rusu Masakage, Ishikawa Akimitsu, Hikohime, Gyokuju-in, Kokubun Morishige, Sugime Naomune
Children: Masamune, Kojirō, Senshihime, daughter, Hideo, Hikohime
Date Terumune served as a bushō and sengoku daimyō during the Sengoku period. He held the titles of Junior Fourth Rank (Lower) and Master of the Eastern Capital Office. Terumune served as the sixteenth head of the Date clan based in Mutsu Province. His eldest son was Date Masamune.
The early years
In the ninth month of 1544, Terumune was born as the second son of Date Harumune at the Koori-Nishiyama Castle in the Date District of Mutsu. His mother was Harumune’s formal wife, Kubohime. His childhood names were Hikotarō followed by Sōjirō. It had been promised that his older brother, Chikataka, would become the adopted heir of Iwaki Shigetaka, his grandfather on his mother’s side of the family, so, as the second son, Sōjirō became the successor to the Date clan.
In 1548, the Tenbun Conflict was settled and came to an end. Terumune’s father, Harumune, moved his base to Yonezawa Castle in the Okitama District. Terumune together with his mother, Kubohime, and siblings, moved to Yonezawa. On 3/19 of of 1555, on the day for conferring a peerage, Harumune chose one of the characters from the name of Ashikaga Yoshiteru, the thirteenth shōgun of the Muromachi bakufu, and assigned the name of Terumune to Sōjirō. He celebrated his coming–of-age day when eleven years old.
Succession to Harumune
In 1565, Harumune retired and transferred his role to Terumune whereupon he became the sixteenth head of the family. Terumune remained in Yonezawa Castle in the Okitama District and protected the borders of Uetsu while Harumune and Kubohime moved to Suginome (Fukushima) Castle in the Shinobu District of Mutsu. Retirement in Suginome also served to guard the borders with the Sōma clan and the Ishibashi clan of Shihonmatsu. In the summer of this year, Terumune’s grandfather, Date Tanemune, who had retired to Marumori Castle in the Igu District after defeat in the Tenbun Conflict died at the age of seventy-eight.
Owing to these developments, Nakano Munetoki and his son, Makino Hisanaka, became the most powerful individuals in the Date family. Subsequently, Terumune reached a settlement with Ashina Moriuji, a sengoku daimyō in Mutsu. To seal the alliance through marriage, early in 1566, Terumune overcame the opposition of his father to send his younger sister, Hikohime, to wed the eldest son of Moriuji, Ashina Morioki. At this time, Terumune and Moriuji secretly agreed that, in the event of a conflict between Terumune and Harumune, Moriuji would support Terumune. Thereafter, Terumune wed Yoshihime, the daughter of Mogami Yoshimori (the lord of Yamagata Castle in Dewa Province). Yoshihime was the younger sister of Mogami Yoshiaki. On 8/3 of 1567, Yoshihime gave birth to their first son at Yonezawa Castle in the Okitama District. He received the name of Bontenmaru, and later became Date Masamune.
In the fourth month of 1570, acting upon his desire to rebel against Nakano Munetoki to gain control of the clan, Terumune attacked Makino Hisanaka at Komatsu Castle, resulting in the ouster of both Munetoki and Hisanaka. Those who were uncooperative with Terumune, including Koyanagawa Morimune, Shiroishi Munetoshi, and Miyauchi Munetada, were punished. That same year, when internal conflict arose in the Mogami clan between Mogami Yoshimori and Mogami Yoshiaki (father and son) in the original home of Terumune’s wife, Yoshihime, Terumune sided with Yoshimori to attack Yoshiaki, but Yoshihime urged Terumune to withdraw, so he pulled back his forces.
Consolidation of control
Having garnered control of the clan, Terumune selected and relied heavily upon Oniniwa Yoshinao as a judicial officer. Terumune recognized the abilities of Endō Motonobu, a capable retainer of Nakano Munetoki, and engaged him to lead diplomatic activities. Terumune’s administration, with these two individuals performing instrumental roles, maintained the policies of Harumune including the alliance with the Ashina clan and mediated disputes among various lords in the southern Ouu region. He also sponsored broad diplomatic initiatives. In the seventh month of 1575, Terumune provided a falcon as a gift to Oda Nobunaga and ordered Motonobu to establish friendly relations with Hōjō Ujimasa and Shibata Katsuie through the frequent exchange of correspondence and presents.
Discord in Echigo
The death of Uesugi Kenshin in 1578 gave rise to a succession struggle within the Uesugi clan of Echigo known as the Otate Conflict pitting Kenshin’s adopted son, Uesugi Kagekatsu against Uesugi Kagetora, the son of Hōjō Ujimasu. Terumune entrusted his uncle, Watari Motomune, in battle against the Sōma clan. Based on an alliance with the Hōjō, he joined Ashina Moriuji to fight on the side of Kagetora. The battle, however, ended in victory for Kagekatsu. The allied forces of the Ashina and the Date could not overcome valiant fighting by two brothers, Shibata Nagaatsu and Shibata Shigeie. Nevertheless, at the conferral of honors in the wake of the Otate Conflict, primary recognition was given to Ueda forces led by Kagekatsu’s son instead of the Shibata forces. A retainer of the Uesugi named Yasuda Akimoto attempted to mediate a resolution between Shigeie and Kagekatsu, but, unable to make progress, took his own life to save honor. In 1581, after Shigeie revolted against Kagekatsu, Terumune joined Ashina Moriuji’s successor, Ashina Moritaka, in support of Shigeie, intervening with Shibata Katsuie in Echigo. As the opposing armies entered into prolonged battle, the Shibata Conflict lasted over seven years.
Sōma Moritane and his son, Sōma Yoshitane, proved to be formidable opponents so the tide of the battle did not easily turn in favor of the Shibata. In 1579, Terumune’s eldest son, Masamune, received Megohime, the daughter of Tamura Kiyoaki, as his formal wife, in an effort to cause divisions on the side of the Sōma. In 1582, Terumune succeeded in luring Satō Tamenobu, the lord of Shōsai Castle, to the side of the Date. In 5/17 of 1583, he finally recaptured Marumori Castle, a stronghold that posed the largest obstacle since the Tenbun Conflict. On 1/11 of Tenshō 12 (1584), Terumune attacked Kaneyama Castle. After recovering all of the Igu District, Terumune called for a ceasefire. In the spring of the same year, the warring parties reached a settlement whereby the Igu District in the retirement domain of Terumune’s grandfather, Tanemune, would be held by the Date while the Uda District came under the control of the Sōma clan.
Regaining the southern Ouu region
At this stage, the Date had recovered almost all of the eleven districts that were under their control around the time of Tanemune. This provided the Date the opportunity to exert significant influence over the entire southern Ouu region. In the fourth month of 1583, Terumune’s ally, Shibata Katsuie, lost to Hashiba Hideyoshi at the Battle of Shizugatake and was eliminated. In a letter dated 6/5 of 1583, addressed to his nephew, Iwaki Tsunetaka, he noted that if Hideyoshi’s influence extended to the eastern provinces, he intended to summon assorted daimyō from Ouu to resist their expansion. However, within the southern Ouu region, Satake Yoshishige of Hitachi Province, who was on friendly terms with Hideyoshi, had expanded his influence into the southern portions of the Ashina domain as well as areas to the south of the Iwase, Tamura, and Naraha districts. In 1581, at the Battle of Miyoda, Yoshishige prevailed against Tamura Kiyoaki, achieving the consolidation of the region under the banner of Oushū Unification. It was likely difficult to mobilize daimyō under the Satake for battle against the Toyotomi.
Transfer of duties to Masamune and relations with the Ashina
On 10/6 of 1584, after Ashina Moritaka was slayed by a servant named Ōba Sanzaemon, possibly in connection with troubles involving a homosexual relationship, Terumune became the guardian of Moritaka’s son, Kameōmaru, who became his father’s successor as head of the clan just one month after birth. Terumune used this as an opportunity to transfer control of the Date family to his eldest son, Masamune, and moved to the renovated Tateyama Castle. Thereafter, he aimed to focus on intervening in the affairs of Echigo. After succeeding his father, however, Masamune reconciled with Uesugi Kagekatsu, and discarded plans for the combined forces of the Date, Ashina, and Mogami to intervene in Echigo. This triggered distrust within the Ashina family toward the Date. Based on a letter from Kamikōriyama 仲為, a lord in Oguni, dated on 9/3 of 1589 to Asano Nagamasa, Terumune may have aimed for his second son, Kojirō to become the next head of the Ashina family instead of Kameōmaru. This is tied to a mutual promise to establish relations between the families through adoption that Terumune made with Ashina Moriuji (Moritaka’s adoptive father) prior to his death. Opposed by Satake Yoshishige, this plan failed to materialize and led to distrust between the Date and Ashina clans, hastening Terumune’s retirement. Alternatively, after the unexpected death of Moritaka, the ensuing chaos among the Ashina attracted Terumune’s attention, and based on discussions with his younger step-brother, Satake Yoshishige, planned to avoid chaos among their families following the sudden death of Moritaka by cooperating together while Terumune was still healthy to transfer control of the Date clan to a successor. While Terumune remained healthy, Yoshishige did not desire confrontation with the Date who wielded significant power in the southern Ouu region. Accordingly, it was in the interest of both families to have a cooperative relationship.
In the spring of 1585, Masamune responded to a demand from his father-in-law, Tamura Kiyoaki, for Ōuchi Sadatsuna, the lord of Obama Castle who earlier became independent from the Tamura and associated with the Date and Ashina, to return under the command of the Tamura clan. With respect to previous disputes with the Ōuchi clan, the Tamura were dissatisfied with and refused to abide by a proposal for reconciliation put forward by Terumune, and incurred attacks by the Ōuchi backed by Ishikawa Akimitsu, Iwaki Tsunetaka, and Date Shigezane. Owing to Sadatsuna’s refusal to abide by Terumune’s verdict, Masamune issued an order to eliminate the Ōuchi. Although Sadatsuna requested mediation with the widow of Ashina Moritaka (Terumune’s younger sister, Hikohime, the mother of Kameōmaru), Masamune suddenly invaded the Ashina domain in the Battle of Sekishiba. After failing in this effort, Masamune made an additional attack against a cousin of Sadatsuna named Nihonmatsu Yoshitsugu, the lord of Nihonmatsu Castle. Masamune’s willingness to rapidly change course to ferocious military action threatened to destroy the diplomatic atmosphere created by Terumune in the southern Ouu region.
Treachery of the Nihonmatsu and sacrifice of Terumune
In the tenth month of 1585, Yoshitsugu offered to surrender to Masamune, and, through the offices of Terumune and his uncle, Date Sanemoto, Yoshitsugu accepted a settlement requiring him to relinquish all of his territory with the exception of five villages. On 10/8 of 1585, Yoshitsugu visited Terumune at Miyamori Castle to express his gratitude for the mediation, but, after the meeting, as Terumune was seeing Yoshitsugu out from the castle entrance, Yoshitsugu and his retainers thrust swords at Terumune and detained him. Date Shigezane and Rusu Masakage called upon soldiers in an effort to surround them from afar, but on the Takada Plain along the Abukuma River that served as the border with the Nihonmatsu territory, Terumune yelled to his retainers not worry about him and to fire upon the enemy for the honor of the family, whereupon the Date forces fired in unison, killing Terumune, Yoshitsugu, and all of the Nihonmatsu forces with them. Hearing the news while out engaging in falconry, by the time that Masamune arrived at the scene, the confrontation was over. Terumune died at the age of forty-two. According to other accounts, Yoshitsugu may have stabbed Terumune knowing that Masamune had come to the scene committed to a showdown, or Masamune himself may have shot Yoshitsugu and Terumune. After Terumune’s remains were interred at the Shifuku Temple, three of his retainers are said to have sacrificed themselves for their master.
The death of Terumune was followed by a rapid deterioration of relations with neighboring families of influence. Terumune’s demise further led to an assortment of diplomatic and military problems for the clan. It spurred Satake Yoshishige to make a full-scale intervention in Oushū, and resulted in the alienation of allies such as Ishikawa Akimitsu. Late in 1585, in the Battle of Hitotoribashi, the Date clan suffered defeat at the hands of Satake forces and local daimyō from the southern Ouu region. After the death of Kameōmaru in the third month of 1587, the side backed by the Date lost in a succession struggle for the Ashina family. Masamune continued to face precarious circumstances until the Date finally achieved victory against an allied army of the Ashina and Sōma clans at the Kōriyama Conflict in 1588.