* Image is for illustrative purposes only.Taira no Sadamori
平貞盛
The Heian Warrior Who Slew His Cousin Taira no Masakado — Ancestor of the Ise Taira Line That Produced Taira no Kiyomori
Description
Life
Taira no Sadamori was a member of the Kanmu Taira clan, born as the son of Taira no Kunika, Deputy Governor (Daijō) of Hitachi Province. Around 935, while serving in the capital as a Left Palace Stable officer, a conflict broke out between his cousin Taira no Masakado and his uncles, and his father Kunika was drawn into the fighting and killed.
The Suppression of Masakado's Rebellion
Rather than seeking immediate revenge after his father's death, Sadamori traveled from the capital to the east. At first he attempted to subdue Masakado together with his uncles, but was thwarted by Masakado's strength, and returned to the capital again in 938. Afterwards, with the assistance of Fujiwara no Hidesato, Deputy Governor of Shimotsuke, he advanced in 940 on Masakado's base in Shimōsa Province and killed him in the battle known as the Battle of Kitayama. For this achievement he was granted the Junior Fifth Rank, Upper Grade, and thereafter held posts including Chinjufu Shōgun (Commander of the Pacification Headquarters), Governor of Tanba, and Governor of Mutsu, and was called the "Taira General."
Lineage and Descendants
Among Sadamori's descendants, the line of his fourth son, Korehira, settled in Ise Province and became the founding line of the Ise Taira, from whose descendants Taira no Kiyomori emerged. The same line is also said to have produced Hōjō Sōun, who founded the Later Hōjō clan in the Sengoku period. Sadamori is thus positioned as the starting point of a warrior lineage running from the late Heian period into the Sengoku period.
Later Reputation
Taira no Sadamori is counted among the key figures in the history of the formation of the warrior class in the Heian period, both as a meritorious figure who suppressed the rebellion of Taira no Masakado and as the ancestral founder of the lineage leading to the Ise Taira and the later regime of Taira no Kiyomori.