Taira no Tadatsune (平忠常)
TAIRA no Tadatsune was a samurai lived during the Heian period. His father TAIRA no Tadayori, who was Mutsu no kuni no suke (officer in charge of regional administration in Mutsu), was the ancestor of Boso-Heishi (Taira clan).
His grandfather TAIRA no Yoshifumi settled in Muraoka, Musashi Province and called himself Goro MURAOKA, who possessed shoryo (territory) in the greater part of Soma County, Shimousa Province. His father Tadayori was also renowned as a powerful samurai in Kanto region. Tadatsune took over the sphere of influence built by his grandfather and father and possessed vast shoryo in Hitachi Province, Kazusa Province and Shimousa Province. He was appointed to Kazusa no suke (Assistant Governor of Kazusa Province) (this is accorging to "Nihongi Ryaku" [Summary of Japanese Chronologies] and it was Shimousa no gonsuke [officer of regional administration in Shimousa] according to "Otoku Gannen Kodaiki" [The Chronicle of the Emperors in Otoku era]) and Oryoshi (government official of police and military affairs) in Musashi Province (there is another theory that he was not appointed to these posts and professed to be appointed). Although several genealogies show that he called himself Kojiro CHIBA in Chiba County, Shimousa Province, the truth is unknown. There is a trace that he left for the capital to serve FUJIWARA no Norimichi (the second son of FUJIWARA no Michinaga). Tadatsune behaved outrageously with backing of the mighty military power and it is said he did not pay his taxes and disobeyed kokushi (provincial governor).
The battle with government army
Tadatsune caused an event that he attacked kokufu (provincial office) in Awa Province in June, 1028 and burned to murder Awa no kami (Governor of Awa Province) TAIRA no Koretada. Although the origin of the event is unknown, it could be the rising antagonism to Zuryo (the head of the provincial governors). The Imperial Court commanded to hunt down and kill Tadatsune and dispatched TAIRA no Naokata as an envoy to search and kill him. Tadatsune put up stubborn resistance to the government army. The battle had spread throughout three provinces in Boso, which became impoverished terribly due to the damage of the battle and forcible requisitions by the government army.
(The TAIRA no Tadatsune War)
TAIRA no Naokata was dismissed and MINAMOTO no Yorinobu in the position of Kai no kuni no Kami (officer in charge of regional administration in Kai) was appointed to be the envoy instead in October, 1030. Since Tadatsune's troops had been exhausted from the long battle, he entered into priesthood with a posthumous Buddhist name Tsuneyasu in Spring of 1031, and then surrendered himself to Yorinobu with his two children and his followers. In June of the same year, he was died of disease in Nogami, Mino Province on the way to being taken to the capital. After Tadatsune had been beheaded to expose his severed head in Kyoto, his head was returned to his family. His children, TAIRA no Tsunemasa and TAIRA no Tsunechika were forgiven.
Tadatsune's descendants remained as powerful samurai in Boso Peninsula and formed the Kazusa clan and the Chiba clan which became gokenin (an immediate vasal of the shogunate) in the Kamakura bakufu (Japanese feudal government headed by a shogun) afterwards.