Though emperor of Japan for only 3 years, Goshirakawa (1127-1192) continued to attend to affairs of state for over 30 years from the safety of a monastery. His reign was beset by civil wars.
Born Masahito, Goshirakawa was the fourth son of Emperor Toba and Fujiwara Akiko (Shoshi). He ascended the throne as Japan's seventy-seventh emperor in 1155, toward the end of what is often called the period of "cloister government," or the Insei system. Under this system the titular sovereign would abdicate at his own pleasure, placing a suitable and docile heir upon the throne, and he would continue to direct affairs of state from the retreat, or cloister. Most of the "cloistered emperors" then "entered religion" and were given the appellation of Hō-ō, or Sacred Ruler, which gave them some protection against secular dangers.
The effectiveness of the Insei system lasted for about 70 years, from 1086 to 1156, although the system survived in form for a little longer. After 1156 it lost much of its political significance, because almost the last shred of power had been torn from both titular and cloistered emperors by the rising military clans.
After Goshirakawa became a cloistered emperor, these military clans and even armed monks of various monasteries made use of him in their struggle for supremacy. Each clan claimed to be the protector of the throne, and Goshirakawa stood as the symbol of a sovereign power that he was unable to wield. During the last half of the 12th century a transfer of power took place, from the imperial court and nobility to the land-owning classes. New power centers formed in the provinces which based their claims upon the possession of manors and the control of armed forces. At that time the most powerful clans were the Fujiwaras, the Minamotos, and the Tairas.
Soon after Goshirakawa's enthronement, the civil war of the Hogen era broke out in 1156. Following his abdication, warrior families rapidly gained power, and Kyoto, the imperial capital, was thrown into confusion, often as a result of armed clashes among military clans. First the fighting took place between different factions of the Fujiwara clan, each supporting a different emperor. But in the Heiji Rising of 1159-1160 warriors of the Fujiwaras, the Tairas, and the Minamotos were engaged in plots and counterplots. Both former emperor Goshirakawa and Emperor Nijo were seized and detained under strict guard by different groups of warriors during the disturbances.
Goshirakawa attempted to play one military clan against another, hoping to maintain the prestige and power of the imperial court. The military families were, however, too powerful for the cloistered former emperor to control, and the imperial court had to grant Minamoto Yoritomo's request entrusting him with the administration of territories conquered by him and his followers during the civil wars.
Goshirakawa died of illness in the spring of 1192. During his lifetime Minamoto Yoritomo was unable to obtain the imperial commission as sei-i tai shogun (barbarianquelling generalissimo), a position which carried practically dictatorial powers and which he ardently desired both for its prestige and for its practical advantage. But after Goshirakawa's death youthful Gotoba (reigned 1184-1198) was readily persuaded to make the appointment. Thus began the shogunate that was to control Japan for most of the next 7 centuries.
A detailed discussion and cogent analysis of Goshirakawa and the Insei system is in Sir George B. Sansom, A History of Japan, vol. 1 (1958). For general background on the development of the early feudal system and of the shogunate see Edwin O. Reischauer and John K. Fairbank, East Asia: The Great Tradition (1960).