There was a possibility that Prince Shioyaki would succeed to the Imperial Throne in view of the facts that he was the husband of Imperial Princess Fuwa, a Princess of Emperor Shomu, that Prince Shioyaki himself was a grandchild of Emperor Tenmu, and that he was supported by such members of the Fujiwara clan as Toyonari and Nagate.
聖武天皇の皇女・不破内親王の夫で塩焼王自身も天武天皇の皇孫であることや豊成・永手といった藤原氏内部からの支持もあった塩焼王には皇位継承の可能性があった。