When his empress-consort (kōgō) died, his son, Imperial Prince Munehito, who had become Crown Prince (and later became Emperor Toba) was taken to be raised by Horikawa's father, the retired Emperor Shirakawa.
Horikawa died at age 29 in Kajō 2, on the 19th day of the 7th month 1107. He had reigned 20 years—seven years in the nengō Kanji, two years in Kahō, one year in the nengō Eichō, two years in Jōtoku, five years in the nengō Kōwa, two years in Chōji, and two years in the nengō Kajō.
Horikawa is buried amongst the "Seven Imperial Tombs" at Ryōan-ji in Kyoto. The mound which commemorates the Emperor Horikawa today named Kinugasa-yama. The emperor's burial place would have been quite humble in the period after Horikawa died. These tombs reached their present state as a result of the 19th century restoration of imperial sepulchers (misasagi) which were ordered by Emperor Meiji.
Emperor Horikawa was succeeded by his son, Munehito, who would take the name Emperor Toba.
Kugyō (公卿) is a collective term for the very few most powerful men attached to the court of the Emperor of Japan in pre-Meiji eras. Even during those years in which the court's actual influence outside the palace walls was minimal, the hierarchic organization persisted.
In general, this elite group included only three to four men at a time. These were hereditary courtiers whose experience and background would have brought them to the pinnacle of a life's career. During Horikawa's reign, this apex of the Daijō-kan included: