Daigo's grandfather, Emperor Kōkō, had demoted his sons from the rank of imperial royals to that of subjects in order to reduce the state expenses, as well as their political influence; in addition, they were given a family name Minamoto. As such, Daigo was not born as a royalty and was named Minamoto no Korezane (源維城) until 887, when Daigo's father, Minamoto no Sadami (formerly Prince Sadami), was once again promoted to the Imperial Prince and the heir to the throne. Afterwards, his personal name ("imina") was changed to or "Ono-tei" before his ascension of the Chrysanthemum Throne.