As a tentative explanation for why she intervened, Yoritomo had served Empress Dowager Josaimonin as a Kurodo (Chamberlain), and it is considered possible that he worked directly for Ike no zenni, who belonged a family of Atsuta Daiguji, that was a vassal of Empress Dowager Taikenmonin (the mother of both retired emperor Goshirakawa and Josaimonin, meaning her family had also served their lady's daughter, Josaimonin), while serving there.
この背景には頼朝が上西門院の蔵人をつとめていたため、上西門院とその近臣・熱田大宮司家が待賢門院（後白河上皇・上西門院の母）近臣家出身の池禅尼に働きかけた可能性が考えられる。