He married FUJIWARA no Takako, fifth daughter of FUJIWARA no Michinaga and Yorimichi's half sister) to build a close relationship with the Fujiwara clan, and became udaijin (minister of the right) in 1069 to form a basis for the Murakami-Genji to go into politics.
藤原道長の五女・藤原尊子（頼通の異母妹）を妻に娶って藤原氏と密接な関係を築き、1069年（延久元年）右大臣となって村上源氏の政界進出の基を築いた。