Mr. Sasaki - Sasakiuji

A powerful clan in Omi descended from the Uda Genji. They ruled over Sasaki Manor in Gamo County, Omi Province (Omihachiman City, Shiga Prefecture) and called themselves the Sasaki clan. During the time of Hideyoshi, they served Minamoto no Yoshitomo during the Heiji Rebellion (1159), and were pursued by the Taira clan and temporarily fled to Shibuya Manor in Sagami Province (near Fujisawa, Yamato, and Ayase City, Kanagawa Prefecture). In 1180 (Jisho 4), they responded to Minamoto no Yoritomo's uprising and made a distinguished contribution to the pursuit and slaying of the Taira clan, and their son Sadatsuna was appointed as the guardian of Omi. Later, the Sasaki clan briefly held the position of shugo in various provinces, with Sadatsuna being appointed shugo of Iwami, Oki, and Nagato, and Sadatsuna's younger brother Tsunetaka being shugo of Awaji, Awa, and Tosa. After the Jōkyū War (1221), Nobutsuna succeeded as head of the family, and the line of his third son Yasutsuna became the main line of the Sasaki clan, and under the name of the Rokkaku clan, they continued to hold the position of shugo in Omi for generations from the Kamakura period to the Sengoku period. After the Onin War (1467-77), Takayori was hunted down by Shoguns Ashikaga Yoshihisa and Yoshiki (Yoshitane), but his son Sadayori served Shogun Yoshiharu and was made quasi-kanrei (regent). In 1568 (Eiroku 11), the clan was attacked and defeated by Oda Nobunaga, and was soon destroyed. The Sasaki clan produced many branches during the Kamakura period, but the line of Yasutsuna's younger brother Ujinobu called himself the Kyogoku clan, and expanded its power based in the northern part of Omi Province. In the early stages of the Nanboku-cho civil war, Takauji (Doyo) temporarily became the guardian of Omi. Later, they became the Samurai-dokoro Shoshi of the Muromachi Shogunate, and as one of the four offices, they became powerful enough to surpass even the Rokkaku clan, but after the Onin War, they gradually declined due to internal strife within the clan, rebellions by their vassals, and conflicts with the Rokkaku clan, and their influence was taken by the Azai clan. Later, during the time of Takatsugu, they served Oda Nobunaga and Toyotomi Hideyoshi, reviving the Kyogoku clan and becoming a modern daimyo.

[Osamu Tashiro]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

宇多源氏(うだげんじ)の流れをくむ近江(おうみ)の豪族。近江国蒲生(がもう)郡佐々木荘(ささきのしょう)（滋賀県近江八幡(おうみはちまん)市）を領して佐々木氏を称した。秀義(ひでよし)のとき、平治(へいじ)の乱（1159）で源義朝(みなもとのよしとも)に属し、平氏に追われて一時相模国(さがみの)渋谷荘(しぶやのしょう)（神奈川県藤沢・大和(やまと)・綾瀬(あやせ)市近辺）に逃れた。1180年（治承4）源頼朝(よりとも)の挙兵に応じて平氏追討に功をたて、その子定綱(さだつな)は近江の守護に任じられた。またその後、定綱が石見(いわみ)・隠岐(おき)・長門(ながと)、定綱の弟経高(つねたか)が淡路(あわじ)・阿波(あわ)・土佐(とさ)の守護に任じられるなど、佐々木一族は一時各国の守護を兼ねた。承久(じょうきゅう)の乱（1221）ののち信綱(のぶつな)が家督を継ぎ、その三男泰綱(やすつな)の系統が佐々木氏の嫡流となり、六角(ろっかく)氏を称して鎌倉時代から戦国時代に至るまで、ほぼ一貫して近江の守護を代々継承した。応仁(おうにん)の乱（1467～77）ののち高頼(たかより)が将軍足利義尚(あしかがよしひさ)・義材(よしき)（義稙(よしたね)）の追討を受けたが、その子定頼(さだより)は将軍義晴(よしはる)に仕え、管領(かんれい)に準ぜられた。1568年（永禄11）織田信長に攻められて敗れ、まもなく滅亡した。佐々木一族は鎌倉時代に多くの庶流を分出したが、なかでも泰綱の弟氏信(うじのぶ)の系統は京極(きょうごく)氏を称し、近江国の北部を基盤に勢力を伸長し、南北朝内乱初期には高氏(たかうじ)（導誉(どうよ)）が一時近江の守護となった。その後、室町幕府の侍所所司(さむらいどころしょし)ともなり、四職(ししき)の一として六角氏をもしのぐほどの勢力となったが、応仁の乱ののち、一族の内訌(ないこう)や家臣の叛乱(はんらん)、六角氏との抗争などのためしだいに衰退し、浅井(あさい)氏に勢力を奪われた。その後、高次(たかつぐ)のとき織田信長、豊臣(とよとみ)秀吉に仕えて京極氏を再興し、近世大名となった。

［田代　脩］

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