Revolt of TAIRA no Tadatsune (平忠常の乱)
The revolt of TAIRA no Tadatsune occurred in the Boso peninsula (Kazusa, Shimousa, Awa Provinces) in the Heian period. It was a massive rebellion that happened in Kanto Region which had been peaceful for a long time since Taira no Masakado Rebellion, in the Heian period.
TAIRA no Tadatsune who was a descendant of TAIRA no Masakado raised a revolt and the Imperial Court dispatched a punitive force, but they could not suppress it for over three years. When a dominant Samurai, MINAMOTO no Yorinobu, was appointed, Tadatsune was surrendered. Due to this revolt, the three Boso provinces were ruined badly. It is also called Chogen Rebellion.
Background
TAIRA no Yoshifumi was called Goro MURAOKA and was based in the Soma country, Shimousa Province and extended power with his son TAIRA no Tadayori and grandson Tadatsune over three generations. Tadatsune owned a large territory in Kazusa Province, Shimousa Province and Hitachi Province, behaved outrageously and did not obey orders of the Kokushi (provincial governor) nor fulfill his obligations to pay taxes.
In June, 1028, an incident occurred in which Tadatsune burned TAIRA no Koretada, Awa no kami (Governor of Awa Province), to death. Its cause is not clear, but it seems that this was because of the deepened confrontation between Zuryo (provincial governor) and Tadatsune, the resident land holder. Tadatsune subsequently occupied the kokuga (provincial government office compounds) in the Kazusa province. The wife and children of Tamemasa INUKAI, Kazusa no suke (Assistant Governor of Kazusa Province), escaped to Kyoto and the kokujins (provincial warriors) in Kazusa Province who saw this cooperated with Tadatsune and the rebellion extended to the three Boso provinces (Kazusa, Shimousa and Awa). At that time, local powerful clans (local military aristocracies) often behaved disaffectedly to the kokuga (provincial government office), but it was overlooked due to the private relationship with central dominant nobilities, so an imperial decree to hunt down and kill Tadatsune was rarely issued.
The incident was reported to the Imperial Court, and MINAMOTO no Yorinobu, TAIRA no Masasuke, TAIRA no Naokata and NAKAHARA no Narimichi were nominated as tsuitoshi, envoys to search and kill Tadatsune. FUJIWARA no Sanesuke, Minister of the Right, recommended Yorinobi at the Jin no sadame (ancient cabinet council). Tadatsune served Yorinobu when he was appointed as Hitachi no suke and Yorinobu thought that he was best suited to settling the situation peacefully. Other Kugyos (high court nobles) agreed with him, but TAIRA no Naokata, Uemon no shojo, kebiishi (official with judicial and police powers), and NAKAHARA no Narimichi, Zaemon no shochi (junior assistant lieutenant), kebiishi, were appointed as tsuitoshi with the approval of Emperor Goichijo. It was FUJIWARA no Yorimichi, chief adviser to the Emperor, who appointed Naokata as tsuitoshi. Naokata was in the position of a direct descendant of Taira no Sadamori and had cooperated with Hitachi-Heishi (Taira clan) which were also descendants of Taira no Sadamori. Hitachi-Heishi had an adversarial relationship with the Taira clan of Yoshifumi line, based in Musashi and Shimousa for many years. Naokata was a Kenin (retainer) of Yorimichi and it is assumed that he asked Yorimichi to assign him to Tsuitoshi. Under the official recognition of the state, Naokata succeeded in obtaining the position to exclude the Taira clan of Yoshifumi line, including TAIRA no Tadatsune. In August, the roto (retainer) of Tadatsune who infiltrated Kyoto was captured. The roto had a letter addressed to FUJIWARA no Norimichi (the private master of Tadatsune), minister of the center, reporting the injustice of the order to track down and kill Tadatsune. TAIRA no Naokata and NAKAHARA no Narimichi selected a "Kitsujitsu" (lucky day) and they left Kyoto with their 200 soldiers at 10 p.m. on August 5, about 40 days after their appointment. In spite of midnight, many spectators gathered to see them off. In the next year, TAIRA no Koretoki, the father of Naokata, was appointed as Kazusa no suke and the punitive force got into full swing. Tadatsune, regarded as a rebel by the state, was forced to resist to the bitter end.
The tsuitoshi, NAKAHARA no Narimichi was inactive and his army stayed in Mino Province on the way to Kanto because his mother was sick. The details of the battle are unknown, but the relationship between passive Narimichi and active Naokata worsened, the punitive force made a poor fight and could not suppress the rebellion at all. In February, 1029, the Imperial Court issued a kanpu (official document from Dajokan, or Great Council of State) to strengthen the punitive force, but the suppression did not made progress. Narimichi was removed from his post for the reason that he failed to report to the imperial court in December of the same year.
In March 1030, Tadatsune attacked the kokuga and ejected FUJIWARA no Mitsunari, Awa no kami (Governor of Awa Province). The Imperial Court appointed TAIRA no Masasuke to the substitute Awa no kami, but he could not leave for the appointed province because he was in the middle of repeated fighting with TAIRA no Munetsune of the same clan. Tadatsune holed up in a military fortress in Ishimi, Isumi County, Kazusa Province and continued resistance. The revolt prolonged and Kazusa Province, Shimousa Province and Awa Province where battles were fought were exhausted.. It is said that FUJIWARA no Tameyori, the Shimousa no kami, was subject to famine and his wife and children died.
In September of the same year, the frustrated imperial court recalled TAIRA no Naokata and appointed MINAMOTO no Yorinobu, Kai no kuni no Kami (officer in charge of regional administration in Kai) as tsuitoshi and ordered suppression of Tadatsune. Yorinobu did not depart soon, but after making good preparations, he left down for Kai Province with his son, Ipposhi. As a result of long battle, the army of Tadatsune was war-worn. In the spring of 1031, when Yorinobu was to leave for Kazusa Province, Tadatsune entered into priesthood and surrendered with his children and followers. Nobuyori headed back to home with Tadatsune, but in June of the same year, Tadatsune died of illness in Nogami, Mino Province. Nobuyori beheaded Tadatsune and returned to Kyoto. Tadatsune's head was exposed, but it was returned to his followers since the head of Koin (person of surrender) should not be exposed and the sins of Tadatsune's children TAIRA no Tsunemasa and TAIRA no Tsunechika were forgiven. In 1032, Yorinobu was appointed Mino no kami due to his achievement.
It is said that Tadatsune, who did not yield to the conquest of TAIRA no Naokata, simply surrendered when Yorinobu participated because Tadatsune was a kenin (retainer) of Yorinobu ("Konjaku Monogatari (Shu)" (The Tale of Times Now Past)).
The three provinces in Boso (Shimousa Province, Kazusa Province and Awa Province), the major battle fields of the rebel, were badly suffered. According to the report of Tatsushige FUJIWARA, Kazusa no kami, the area of rice fields in Kazusa Province was used to be 22,000-cho, but reduced to 18-cho. But, at the same time, it is clearly stated that it was caused by plundering by the tsuitoshi TAIRA no Naokata and country soldiers who formed the imperial court army ("Sakeiki" (A Diary of MINAMOTO no Tsuneyori, the section of October 24, 1034)).
After the stabilization of this revolt, many of the Bando-Heishi clan went under control of Yorinobu and it was a key factor that Seiwa-Genji extended their power in Togoku (the eastern part of Japan, particularly Kanto region).