It is said that he married his Uncle, FUJIWARA no Kamatari's daughter and was adopted by his wife's family and then became the head of Fujiwara clan until Kamatari's biological son, FUJIWARA no Fuhito became an adult.
叔父藤原鎌足の娘を娶って婿養子となり、鎌足の実子である藤原不比等が成人するまで藤原氏の氏上であったといわれている。