Kazusa Hirotsune (上総広常)

Hirotsune KAZUSA was a busho who lived during the end of the Heian period. He was the eighth son (an heir) of TAIRA no Tsunezumi, Kazusa no Gon no suke (provisional vice governor of Kazusa Province). His surname was Taira and his official nanori (announcement of one's name) was TAIRA no Hirotsune. Kazusa no suke Hirotsune was widely used as his name. He was a head of the Soryo (governing) family of the Taira clan of Boso Province and it is said that MINAMOTO no Yoritomo succeeded to raise an army owing to the support from Hirotsune, the most powerful man in the Togoku (eastern country).


The Kazusa clan possessed territories in two provinces, Kazusa Province and Shimousa Province, as the Kazusa no suke (Assistant Governor of Kazusa Province) or the Kazusa no Gon no suke. Kazusa province was Shinno-ningoku (provinces whose gubernatorial posts were reserved as sinecures for imperial princes); therefore, Suke was essentially the head of Kokufu (ancient provincial offices).

Hirotsune was a roto (retainer) of MINAMOTO no Yoshitomo who had his headquarters in Kamakura. During the Hogen War in 1156, he took the side of Yoshimoto and during the Heiji War in 1159, he followed MINAMOTO no Yoshihira, the eldest son of Yoshitomo, and performed well. He was one of Yoshihira 17 horse soldiers. He returned to his territorial province, avoiding pursuers of the Ise-Heishi clan after losing the Heiji War. After Yoshitomo lost the war, Hirotsune followed the Heike clan; however, the internal conflict between Hirotsune, an heir to Tsunezumi, and his older brothers, Tsunekage and Tsuneshige, regarding the reigns of the Kazusa clan developed after his father, Tsunezumi, died. This feud between the brothers lasted until around the time when Yoritomo raised an army. In November, 1179, when FUJIWARA no Tadakiyo, a powerful member of the Heike, was appointed the Kazusa no suke, Hirotsune fought with him over state affairs and was expelled by TAIRA no Kiyomori. Moreover, it is thought that the political situation surrounding Hirotsune, such as the expansion of power of FUJIWARA no Chikamasa, a relative of the Heike by marriage, forced Hirotsune to defeat the Heike.

In August, 1180, Hirotsune raised an army to defeat the Heike and wiped out the Heike's party in Kazusa Province when MINAMOTO no Yoritomo had attempted to re-raise an army in Awa Province after losing the Battle of Ishibashiyama and joined forces with Yoritomo's force and his 20,000 horse soldiers. According to "Azuma Kagami" (The Mirror of the East), using a quote from "Shomon Ki" (tale of Masakado), Hirotsune first had "double intentions" in his mind in trying to kill Yoritomo depending on the situation; however, he changed after seeing Yoritomo's resolute attitude and tried to corroborate with Yoritomo. Moreover, "Azuma Kagami" described Hirotsune's soldiers as being 20,000 even though they were 10,000 and 1000 in "Enkeihon The Tale of the Heike" and "Genpei Tojoroku"(a record of Genpei battles), respectively.

In November of the same year, Hirotsune insisted on subduing the Satake clan of the Hitachi-Genji clan of Hitachi Province to Yoritomo who was going to the capital after winning the battle of Fujikawa. Hirotsune also had a relationship by marriage with the Satake clan and proposed a meeting to Yoshimasa SATAKE and Hideyoshi SATAKE; however, Hideyoshi SATAKE said that he could not come up immediately, and confined himself in the Kinsa-jo Castle. Yoshimasa SATAKE eventually came to meet Hirotsune; however, Hirotsune killed him after Hirotsune called him to meet on the bridge without their retainers. Later, Yoritomo's force attacked Hideyoshi SATAKE confined at the Kinsa-jo Castle and defeated Hideyoshi (the Battle of Kinsa-jo Castle).

In the chapter "June 19 (the old calendar), 1181," of "Azuma Kagami," Hirotsune, possessing by far the strongest force among Yoritomo's vassals, was described as a person who was often rude and that "he has never shown his respect for me after all these years over three generations with Yoritomo's family, both officially and privately" toward Yoritomo. And it was also written that he did not excercise "Geba no rei" (dismounting from a horse to show respect) and was rude to other retainers; moreover, he almost fought with Yoshizane OKAZAKI rgarding to Suikan (everyday garment worn by commoners in ancient Japan) given by Yoritomo. However, "Azuma Kagami" was compiled in the late Kamakura period so it is unclear how accurate the stories were.

Then, in December of 1183, Yoritomo ordered Kagetoki KAJIWARA to assassinate Hirotsune while he was playing a Sugoroku game for the reason that Hirotsune planned a rebellion. Tsune KAZUSA, who was an heir, committed suicide and territories possessed by the Kazusa clan was confiscated. Later after these incidents, although a ganmon (Shinto or Buddhist prayer) was found in Hirotsune's amour, even one sentence indicating a plan of rebellion was not discovered. The ganmon only contained a prayer to wish for Yoritomo's victories; thus, Yoritomo regretted to assassinated Hirotsune and released Hirotsune's family staying at Tsunetane CHIBA immediately. However, it is said that family's large territories had already been divided and given to the Chiba clan, the Miura clan and so on, therefore, the family was never able to recover their territories. The most of people at present thought that the remission was expected to happen at the time.

According to "Gukansho" (Jottings of a Fool) (volume 6), when Yoritomo came to the capital for the first time in 1190, Hirotsune continuingly mentioned to Emperor Goshirakawa that he did not understand why the Emperor's concern was only for the welfare of the Imperial Court but did not know who could control forces active in Togoku. Moreover, it was also mentioned that he was killed because he wished for the independency of the Kanto region rather than defeating the government led by the Taira clan.

The site of Hirotsune's house

The precise site of Hirotsune Kazusa's castle remains unknown; however, exploration of castle sites built during the medieval period has been conducted in recent years around Ohara-machi Town, Isumi-gun County, Chiba Prefecture (presently known as Isumi City) and Onjuku-machi Town and progress was made in identification of the site. The reports based on the explorations are indicated in references below.

"Where is the castle site of Kazusa no suke Hirotsune," 1993, Shinpei KATO, "Archeological essays: Professor Hiroshi SHIOMI's retirement commemorative theses" published by Professor Hiroshi SHIOMI retirement commemorative organization stored in the Department of Archaeology, Graduate School of Letters, Hiroshima University.

[Original Japanese]