With the outbreak of the Hōgen Rebellion in 1156, the members of the Minamoto and Tairasamurai clans were called into the conflict. Yoshitomo and Taira no Kiyomori both threw their support behind Emperor Go-Shirakawa and Fujiwara no Tadamichi, while Yoshitomo's father, Minamoto no Tameyoshi, sided with the retired Emperor Sutoku and Fujiwara no Yorinaga. Yoshitomo, defeating his father and the forces of Sutoku and Yorinaga, became head of the Minamoto clan and established himself as the main political power in the capital of Kyoto. However, despite attempts to have his father pardoned, Tameyoshi was executed. In the aftermath of the rebellion, the Taira and Minamoto became two of the strongest and most influential clans in Japan, which turned the two clans into bitter rivals.[1]
Heiji Rebellion
In the first months of 1160 while Taira no Kiyomori was absent from the capital of Kyoto, Yoshitomo and Fujiwara no Nobuyori placed Go-Shirakawa under house arrest and killed his retainers, including the scholar Fujiwara no Michinori, in what is called the Heiji rebellion. The civil war wasn't to go on for very long as Kiyomori declared his support for the Emperor and rapidly defeated the rebel forces within the span of a month.[1]: 255–258
While making his escape from Kyoto, Yoshitomo was forced to sacrifice his son Tomonaga to buy time. Even so, Yoshitomo was eventually betrayed and murdered while taking a bath. Three of his surviving sons, Yoritomo, Yoshitsune and Noriyori, were spared execution and exiled by the victorious Kiyomori. However, Yoshitomo's allies Yoshihira and Nobuyori were both executed.[2]
His grave in Aichi Prefecture is surrounded on all sides by wooden swords (bokuto), as by legend his last words were "If only I'd had a bokuto...".
