Jōwa Incident

The Jōwa Incident (承和の変^?, Jōwa no Hen) was a Japanese succession dispute that occurred in 842, during the early Heian period. Fujiwara no Yoshifusa's nephew, the future Emperor Montoku, took over the role of Crown Prince, while the former crown prince Prince Tsunesada and a number of Yoshifusa's rivals were removed from power. It brought an end to thirty years of uneventful successions that the court had enjoyed by the wishes of Emperor Kanmu and the power of Emperor Saga.

In 823, Emperor Saga abdicated the throne, and his younger brother ascended as Emperor Junna. In 833, the throne passed again to Saga's son, Emperor Ninmyō. At this point, Prince Tsunesada, a son of Junna by Saga's daughter Princess Seishi, was made crown prince. Saga guided the government for almost thirty years, avoiding succession disputes in that time.

During this time, Fujiwara no Yoshifusa of the Hokke gained the confidence of the retired Emperor Saga and his chief consort Tachibana no Kachiko and quickly rose to prominence. Yoshifusa's younger sister Junshi (順子^?) became a wife of Emperor Ninmyō and bore him a son, Prince Michiyasu, the future Emperor Montoku. Yoshifusa wanted this child put on the throne. Tsunesada and his father Junna, uncomfortable with this development, appealed to Saga to allow Tsunesada to leave his position as crown prince, but were refused each time.

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