Imperial Prince Iyo, prince of Emperor Kanmu, was in his father Kanmu's favor while Kanmu was in living and his mother Yoshiko's elder brother FUJIWARA no Otomo was, being as Dainagon (a chief councilor of state), the second-ranking official of Daijokan (Grand Council of State) next to udaijin (minister of the right) FUJIWARA no Uchimaro and boasted of strong political power.
桓武天皇の皇子である伊予親王は父桓武の生前深い寵愛を受けており、また、母吉子の兄藤原雄友は大納言として右大臣藤原内麻呂に次ぐ太政官のNo.2の位置にあり、政治的にも有力な地位にあった。