Watanabe ( and other variants) is a Japanese surname derived from the noble and samurai Watanabe clan, a branch of the Minamoto clan, descending from the Emperor Saga (786-842), the 52nd Emperor of Japan, and refers to a location called 'Watanabe no tsu' which was settled by the Watanabe clan, who took the name of the place. It was located in the medieval period near the mouth of the Yodogawa River in Settsu Province, in present-day city of Osaka.
History
Origin
The surname Watanabe comes from the Watanabe clan founded by Watanabe no Tsuna (953-1025), of the Saga Genji branch of the Minamoto clan, and his official name was Minamoto no Tsuna. He established the Watanabe branch of the Minamoto clan, taking the name from his stronghold at Watanabe no tsu, a port on the Yodogawa River in Settsu Province, and in 1020 he was appointed Tango no Kami (Governor of Tango Province). He was the son of Minamoto no Atsuru (933-953), married to a daughter of the Chinjufu-shōgun (Commander in chief of the defense of the north) Minamoto no Mitsunaka (912-997); he was the grandson of Minamoto no Tsuko (891-942), Musashi no Kami (Governor of Musashi province); was the great-grandson of Minamoto no Noboru (848-918), Dainagon (Chief Councilor of State); great-great-grandson of Minamoto no Tōru (822-895), Sadaijin (Minister of the Left); and was the great-great-great-grandson of the Emperor Saga (786-842), the 52nd Emperor of Japan. He was the stepgrandson of the Chinjufu-shōgun Minamoto no Mitsunaka, a descendant of the Emperor Seiwa (850-881), and having lost his father the year of his birth, he was adopted by Minamoto no Atsushi, a descendant of the Emperor Ninmyō (808-850), and son in law of Mitsunaka. He was companion in arms to his stepuncle Minamoto no Yorimitsu (944–1021), son of Mitsunaka; and is famous for his military exploits in a number of tales and legends. He is known as one of the Four Guardian Kings (Shitennō) of Yorimitsu, referring to the Buddhist Four Heavenly Kings.
Heian period to the Genpei war
Watanabe no Den, great-grandson of Tsuna, received from the Emperor Shirakawa (1053-1129) the hereditary title of Shokan (Governing officer) of the huge Oe no Mikuriya estate, and in Kyoto he inherited the military charges of Takiguchi no musha (Takiguchi warriors Guards of the Imperial Palace), as well as Emonfu (Government office of the Outer Palace Gate Guards) and Hyoefu (Administrative office of Middle Palace Guards).
Dominating Settsu Province as a focal area of maritime transportation in medieval Japan, the Watanabe family spread its influence widely. Their descendants settled in other areas, including Kyushu.
Watanabe Hisashi (1064-1148 or 1154), also called Minamoto no Hisashi, great-grandson of Tsuna, was appointed Kebiishi (Chief of the police and justice), received the title of Shokan (Governing officer) of Uno no Mikuriya estate in Matsuura (Hizen province, in Kyushu) and called himself Matsuura Hisashi. He ruled the County of Matsuura, the province of Iki, and a part of Sonogi district, and is the ancestor of the Matsuura Watanabe branch, Lords of Hirado castle.
The priest Mongaku Shōnin who urged Minamoto no Yoritomo (1147–1199) to start a war against the Taira, and who managed to get a letter from the Emperor Go-Shirakawa (1127–1192) to Yoritomo, requesting that he set up an army and liberate the country from the tyranny of the Taira, which enabled the Minamoto clan to take up arms, was the son of Watanabe no Endo Mochito.
During the Hōgen rebellion (1156), and the Genpei War (1180–1185), the Watanabe sided with Minamoto no Yorimasa (1106–1180), until his death at the Battle of Uji, then with Minamoto no Yoritomo.
At the Battle of Uji (1180), the opening battle of the Genpei War, the Watanabe clan formed with the warrior monks of Miidera Temple most of the Minamoto clan army.