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cloistered rule; government by cloistered emperors
上皇が院政を敷いて権力を握った。
The retired emperor established cloistered rule and seized power.
院政の時代は政治が複雑だった。
The era of cloistered rule was politically complex.
院政によって天皇の権威が弱まった。
Imperial authority weakened due to cloistered rule.