Retired Emperor SHIRAKAWA, who became Daijo Tenno, acted as the guardian of the young Emperor, and ruled personally as Shirakawa-in, and this style of government became known as Insei system (cloistered style).
太上天皇となった白河上皇は、幼帝を後見するために白河院として自ら政務を執り、いわゆる院政が出現した。