There are a couple of theories as to why SOGA no Emishi blocked Prince Yamashiro no oe in his bid for the Imperial Throne; one is that Prince Yamashiro no oe was still young and immature and hated Prince Yashiro no oe's popularity and the other one was that he had to avoid further confrontation with anti- Soga clan forces by allowing the ascent of Prince Yamashiro no oe since the imperial family and the subsequent emperor Suiko were supported by the Soga clan.
蘇我蝦夷が山背大兄王を避けた理由については、山背大兄王がまだ若く未熟であった、あるいは山背大兄王の人望を嫌ったという説と、推古天皇に続いて蘇我氏系の皇族である山背大兄王を擁立することで反蘇我氏勢力との対立が深まる事を避けたかったためという説がある。