The Hōgen Rebellion (保元の乱) was a Japanese civil war fought in 1156 over Japanese imperial succession and control of the Fujiwara clan of regents. However, it also succeeded in establishing the dominance of the samurai clans and eventually the first samurai lead government in the history of Japan.

After the death of the cloistered emperor Toba, the emperor Go-Shirakawa and the retired emperor Sutoku disputed over succession to the throne and continuation of the cloistered government. Fujiwara no Tadamichi, first son of regent Fujiwara no Tadazane, sided with Go-Shirakawa while his younger brother Fujiwara no Yorinaga sided with Sutoku. Each rival side in turn beckoned the Minamoto and Taira clans of samurai. Minamoto no Tameyoshi, head of the Minamoto clan, and Taira no Tadamasa sided with Sutoku and Yorinaga while on the other hand Minamoto no Yoshitomo, first son of Minamoto no Tameyoshi, and Taira no Kiyomori, head of the Taira clan and nephew of Taira no Tadamasa, sided with Go-Shirakawa and Tadamichi.

The forces of Go-Shirakawa defeated the retired emperor Sutoku making the way for emperor Nijo to be appointed to the throne and Go-Shirakawa becoming the new cloistered emperor in 1158. Sutoku was banished to Sanuki province of Shikoku, Fujiwara no Yorinaga was killed in battle, and Minamoto no Tameyoshi and Taira no Tadamasa were executed. Minamoto no Yoshitomo became head of the Minamoto after the death of his father and together with Taira no Kiyomori, succeeded in establishing the two samurai clans as new political powers in Kyoto.

The outcome of the Hogen Rebellion and the rivalry established between the Minamoto and Taira clans led to the Heiji Rebellion in 1159.

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The Kamakura period epic Tale of Hogen is about the exploits of the samurai that participated in the Hogen Rebellion. Together with the Tale of Heiji and the Tale of Heike, they describe the rise and fall of the Minamoto and Taira samurai clans.