His mother was Daishin no Tsubone, a daughter of the Hitachi-nyudo monk Nensai (also called by the names FUJIWARA no Tokinaga and Tomomune DATE), the founder of the Date family.
母は伊達氏の祖と言われる常陸入道念西（藤原時長、伊達朝宗）の娘・大進局。