The appointment was recommended by TAIRA no Munemori who became Toryo (the head) of the Taira clan after the death of TAIRA no Kiyomori for the purpose of discouraging Yoritomo in Kamakura who raised an army in the previous year.
平清盛亡き後平氏の棟梁となった平宗盛の推挙によるもので、前年に挙兵した鎌倉の頼朝を牽制する目的であった。