Minamoto no Mitsumasa (源満政)
MINAMOTO no Mitsumasa (源 満政: dates of birth and death unknown) was a busho (Japanese military commander), who lived during the mid-Heian Period. He was the second son of MINAMOTO no Tsunemoto. MINAMOTO no Mitsunaka, MINAMOTO no Mitsusue, and others were his brothers from the same mother. His sons were MINAMOTO no Tadashige, MINAMOTO no Tadataka, MINAMOTO no Tadakuni, and so on. His official court rank was Jushiinoge (Junior Fourth Rank, Lower Grade), and he held such positions as Kebiishi (officials with judicial and police powers), Saemon no daijo (Senior Lieutenant at the Left Division of Outer Palace Guards, Tsuwamonogura (兵庫) no jo (manager of arsenal bureau), Sama no suke (Vice-minister of the Left Division of Bureau of Horses), Hyobu no sho (Secretary of the Ministry of Military), Jibushoyu (Junior Assistant Minister of the Ministry of Civil Administration), Mutsu no kuni no Kami (Governor of Mutsu Province), Iyo no kuni no Kami (Governor of Iyo Province), Musashi no kuni no Kami (Governor of Musashi Province), and Chinju-fu shogun (Commander-in-Chief of the Defense of the North). He called himself Yashima no daibu, Muraoka no daibu, etc. He was the first generation of the Mitsumasa line, Seiwa-Genji (Minamoto clan). His Imina (personal name) is also written as 満正 (Mitsumasa).
It is said that his name appeared for the first time in an article related to the mobilization carried out in 994 in order to pursue and apprehend the robbers, and this article informed that he was called up together with TAIRA no Koremasa (TAIRA no Sadamori's son) and his nephews, MINAMOTO no Yorichika and MINAMOTO no Yorinobu, and others, in search for the robbers ("Nihongi Ryakuki" (Summary of Japanese Chronologies) and the article of the 6th day of the 3rd month of the 5th year of Shoryaku (old lunar calendar) or the article of April 24, 994) in "Honcho seiki" (Chronicle of Imperial Reigns)). In addition, it is confirmed that a private memorandum record, "Midokanpaku-ki" reported that he frequently presented a horse to FUJIWARA no Michinaga, and he had a residence at Ichijo in the northern periphery of Sakyo-ku, where many upper class court nobles were living. Therefore, it can be inferable that like his elder brothers and nephews, he was one of the rich military aristocrats that belonged to the career provincial official class with vested interest and were closely associated with the family of FUJIWARA no Michinaga. In "Zoku honcho ojoden" (Sequel to the Accounts of Rebirth into the Pure Land) written by Oe no Masahira in the latter Heian Period, his name was also included in 'the prominent figures in the country,' with such other names as MINAMOTO no Mitsunaka, MINAMOTO no Yorimitsu, TAIRA no Korehira, and TAIRA no Muneyori.
Moreover, there exist historical spots and documents that imply his certain linkage with Settsu Province, which was the home base province of the Seiwa-Genji (Minamoto clan) at that time; for example, Hazuhachiman-jinja Shrine located in Takarazuka City, Hyogo Prefecture, is said to have been constructed by Mitsumasa, and there remains a document that registered his visit to Shionoyu-onsen Hot Spring in Nose Town, Osaka Prefecture for the purpose of toji (hot spring cure).
In later time, out of Mitsumasa's descendents, his first son Tadashige's line expanded into a wide range of areas over Mino Province to Owari Province and Mikawa Province, and beginning with the Yajima clan, a lot of clans appeared one after another, such as the Urano clan, Yamada clan, Mizuno clan, Azuke clan, Ogawa clan, Takada clan, Kojima clan, Sado clan, and Kida clan. On the other hand, his second son Tadataka's line principally placed its power base in Omi Province, where the Yoshizumi clan, the Omiwada clan, and others were formed. And the third son Tadakuni's relation with Settsu Province was also documented.