Emperor Tenji passed over his brother for his son in 671, and the brother raised an army, won the throne and had the official history written by his own son

Emperor Tenji first trusted his younger brother, Prince Ōama, and treated him as his heir. As his son Prince Ōtomo grew up, Tenji favoured the son, and in the first month of 671 he made Ōtomo Grand Minister. The Nihon Shoki records that when the dying emperor offered Ōama the succession, Ōama declined, asked that Ōtomo be made heir, said he would renounce the world, and withdrew to Yoshino as a monk. Tenji died at the end of 671 and Ōtomo ran the court at Ōtsu. In the sixth month of 672 Ōama raised troops in the east. The old great clans backed Ōtomo; smaller clans and Ōama's retainers backed Ōama. The war lasted about a month. Ōtomo, aged 24, killed himself at Yamasaki in the seventh month. Ōama took the throne in 673 as Emperor Temmu. The Nihon Shoki, the history that records the war, was compiled under Temmu's son Prince Toneri and presented in 720; it does not record Ōtomo as emperor. Historians accept that it reflects Temmu's side. Later chronicles say Ōtomo did reign. In 1870 the Meiji government added him to the list of emperors as Emperor Kōbun, 1,198 years after his death.