Cloistered rule

The cloistered rule system, or Insei (院政^?) (meaning "monastery administration"), was a specific form of government in Japan during the Heian period. In this bifurcated system, an emperor abdicated, but retained power and influence. Those retired emperors who withdrew to live in monasteries (in) continued to act in ways intended to counterbalance the influence of Fujiwara regents and the warrior class. Simultaneously, the titular emperor, the former emperor's chosen successor, fulfilled all the ceremonial roles and formal duties of the monarchy.

Retired emperors were called Daijō Tennō or Jōkō. A retired emperor who entered a Buddhist monastic community became a Cloistered Emperor (Japanese 太上法皇 Daijō Hōō).

There were retired emperors, including cloistered emperors, both before and after the Heian period, but the notion of cloistered rule as a system usually refers to the practice put in place by Emperor Shirakawa in 1086 and followed by his successors until the rise of the Kamakura shogunate in 1192.

The ritsuryō code allowed retired emperors to exert some limited powers, and there are early examples such as Empress Jitō, Emperor Shōmu and Emperor Uda in the 7th, 8th and 9th centuries respectively.

By the end of the 10th century, the Hokke family of the Fujiwara clan held political power in Japan through the office of the Imperial Regent, and the emperor increasingly became little more than a figurehead. In 1068, Emperor Go-Sanjō became the first emperor in almost 200 years who was not related either by marriage or blood, or both, to the Hokke family. He exerted personal power while the Hokke family was dealing with internal conflicts between Fujiwara no Yorimichi and his brother Fujiwara no Norimichi, and was in a position to issue several laws and regulations, most notably the Enkyū Shōen Regulation Decree, thus weakening the regency. In 1072, however, he fell ill and abdicated in favor of Emperor Shirakawa. He died the following year. Although he did not have time to exert power after his abdication, Sanjō had weakened the regency and paved the way for the practice of cloistered rule.

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