His father, Tadamune was the first son of FUJIWARA no Ietada, who was the second son of FUJIWARA no Morozane who was a child of FUJIWARA no Yorimichi of the Northern House of the Fujiwara clan.
父忠宗は藤原北家藤原頼通の子藤原師実の次子藤原家忠の長子である。