Minamoto no Tadamune (源忠宗)
MINAMOTO no Tadamune (date of birth and death unknown) was a busho (Japanese military commander) from Kawachi-Genji (the Minamoto clan of Kawachi Province) and active during the Heian period. He was also called Gentaro OBU.
He was the third son of MINAMOTO no Yoshitada who was the fourth son (according to another opinion, he was the third son) of MINAMOTO no Yoshiie (Hachimantaro). He called himself Genta (Gentaro) OBU.
Obu' should be written formally as '飫富', however often written as '飯富.'
He established Obu-no-sho (Manor of Obu, in present Sodegaura City, Chiba Prefecture). He became the heir of his uncle MINAMOTO no Yoshimune, and called himself 'Genta,' although he was the third son of Yoshitada ('ta' [太] and 'taro' [太郎] commonly refer to first son).
Official court rank and position
As for Tadamune's official rank and post, according to some records, his post was 'Tachihaki no osa' (captain of the Guards), 'Saemon no Shoi' (Junior Lieutenant of the Left Division of Outer Palace Guards), and 'Kebiishi' (official with judicial and police powers), and his court rank is unknown. However, if he had been given the rank of Goi (Fifth Rank), he would have been called 'Taifu Hogan' (official who served as guard and as Kebiishi at the same time at the fifth rank), therefore, it is considered that his rank was lower than Goi.
Besides, according to some records, he was Hokumen no bushi (the Imperial Palace Guards for the north side), however the period he had served is unknown.
Obu-no-sho
His name is not found in the records of the Hogen War (1156) and of the Heiji War (1159). Considering that, presumably he left the capital during the wars, and went to Kazusa Province and established Obu-no-sho.
Since he did not participated in the Genpei War after MINAMOTO no Yoritomo had raised an army (after year 1180), he was probably dead at that time. However, Obu-no-sho existed at that time.
Therefore, it is considered that Obu-no-sho was established about the middle of the twelfth century.
Descendants
Taihu Hogan MINAMOTO no Suesada,' who was recorded as a commander supporting Heike (the Taira family) in the Genpei War, is said to be a grandson of Tadamune. This supposition is supported by the facts that MINAMOTO no Munesue, a son of MINAMOTO no Suesada, called himself the Obu clan, and that Munesue called himself a descendant of MINAMOTO no Yoshitada, and that Suetada called himself Obu-no-Shoji (administrator of Obu Manor). However, according to another theory, Suesada was from the Mitsumasa line of Seiwa-Genji (the Minamoto clan of descendants of Emperor Seiwa), and Munesue became an adopted son of Tadamune. If this theory is true, Tadamune died in or after 1183.
It is said that Toramasa OBU, a senior vassal of the Kai-Takeda clan, was a descendant of Munesue.