Heiji Rebellion
Minamoto no Yoritomo was exiled by the leader of the Taira clan, Taira no Kiyomori, following the Heiji Rebellion of 1160. In the following years, the Taira clan attempted to consolidate their position, eventually forcing the Emperor Takakura to abdicate in favour of his infant son, Antoku, whose mother was a Taira. Prince Mochihito, brother of Emperor Takakura, felt that the Taira has denied his rightful claim to the throne, and in May 1180, issued an appeal to the Minamoto clan to rise against the Taira. As Yorimoto was married into the Hōjō clan, they helped fund his petition to claim himself as the head of the Minamoto clan.