Kujo-ryu school (the descendants of the Northern House of the Fujiwara clan and a school of Yusoku k (九条流)

The Kujo-ryu school refers to the descendants of the Northern House of the Fujiwara clan, especially, FUJIWARA no Morosuke and to the school of Yusoku kojitsu (court and samurai rules of ceremony and etiquette) handed down the FUJIWARA no Morosuke family.

FUJIWARA no Morosuke was the second son of the Kanpaku (a chief adviser of the Emperor) FUJIWARA no Tadahira and promoted to Minister of the Right (a government position in Japan in the late Nara and Heian periods), however, he finished his life without being appointed to the Sessho (an assistant for either a child emperor or an empress) or Kanpaku due to the existence of his older brother FUJIWARA no Saneyori. However, he wrote books called "Kujo nenchugyoji" (Kujo annual events) which explained necessities in the Imperial Court, as one of the powerful politicians for the sake of descendants.

Descendants of Morosuke were blessed with many girls; thus, the family line monopolized a post of Sessho Kanpaku by becoming maternal relatives of emperors from the period of the Emperor Reizei to the period of the Emperor Goreizei, covering eight long generations of the emperor. Especially, FUJIWARA no Michinaga and his son, FUJIWARA no Yorimichi, controlled the court government for 70 years in tandem and built the regency at the height of its prosperity. Their descendants were called the Mido-ryu school and succeeded a post of Sekkan (regents and advisers) and Toshi Choja (a head of the Fujiwara clan) for generations. It is said that they performed the court ceremony based on "Kujo nenchugyoji" and tried to put themselves in a superior position over other clans in the Imperial society which weighed heavily on its convention.