After the late era of Retired Emperor Shirakawa's government, there were many donations of private estates (owned by a noble, a temple or a shrine) to the retired Emperor's Palace, it caused the Imperial Palace to have an enormous financial base.
さて、白河院政の後期以降、院への荘園寄進が非常に集中するようになり、天皇家は莫大な経済基盤を得ることとなった。