Background
He was born the third son of Fujiwara no Nagara, but was adopted by his powerful uncle Fujiwara no Yoshifusa, who had no sons.
藤原 基経堀川大臣
He was born the third son of Fujiwara no Nagara, but was adopted by his powerful uncle Fujiwara no Yoshifusa, who had no sons.
Mototsune followed in Yoshifusa"s footsteps, holding power in the court in the position of regent for four successive emperors. Mototsune invented the position of kampaku regent for himself in order to remain in power even after an emperor reached maturity. This innovation allowed the Fujiwara clan to tighten its grip on power right throughout an emperor"s reign.
Mototsune is referred to as Shōsen Kō (昭宣公) (posthumous name as Daijō Daijin).
864 (Jōgan 6): Mototsune was named Sangi
866 (Jōgan 8): Chūnagon
870 (Jōgan 12, 1st month): He became Dainagon
872 (Jōgan 14): He was named Udaijin
876 (Jōgan 18): He was named Sesshō
880 (Gangyō 4): He was named Daijō Daijin
884 (Gangyō 8): Mototsune was the first to receive the title Kampaku. 890 (Kanpyō 2, 14th day of the 12th month): retire from Kampaku
February 25, 891 (Kampyō 3, 13th day of the 1st month): Mototsune died at the age of 56.
Mototsune was adopted as son and heir of Yoshifusa. Their children were
Tokihira (時平) (871–909) - Sadaijin
Nakahira (仲平) (875–945) - Sadaijin
Tadahira (忠平) (880–949) - Daijō Daijin, Sesshō and Kampaku
Yoriko (頼子) (?–936), consort of Emperor Seiwa
Kazuko (佳珠子) (?–?), consort of Emperor Seiwa
Onshi (温子) (872–907), consort of Emperor Uda
He was also married to a daughter of Imperial Prince Tadara (son of Emperor Saga).
They had a son. Kanehira (兼平) (875–935) - Kunai-Kyō (宮内卿)
The other children were
Kamiko (佳美子) (?–898), consort of Emperor Kōkō
Yoshihira (良平)
Shigeko (滋子), married to Minamoto no Yoshiari (son of Emperor Montoku).
This member of the Fujiwara clan was the son of Fujiwara no Nagara, who was one of the brothers of Fujiwara no Yoshifusa.