Although some have a different theory, he is the third imperial prince of the Emperor Jomei and Takara no Himemiko (the Empress Kogyoku), and the younger maternal half-brother of the Emperor Tenchi and Hashihito no Himemiko.
舒明天皇の第三皇子で母は宝皇女（皇極天皇）、天智天皇、間人皇女の同母弟であるが、異説もある。