The Hanakura Rebellion: The 1536 Succession That Turned a Monk into a Sengoku Daimyō

In the third month of 1536 (Tenbun 5), in Suruga. Ujiteru, head of the Imagawa house, died suddenly at twenty-four.

With the head fallen and no heir, the headship of the Imagawa house hung in the air.

At this time, Ujiteru's younger brother Sengaku Shōhō (the later Yoshimoto), who was in Buddhist orders, was pressed to decide whether to return to lay life and succeed to the house.

Shōhō was around eighteen. His quiet half-life as a Zen monk turned overnight into a struggle over the seat of a Sengoku daimyō.

Yoshimoto was born a son of Imagawa Ujichika and entered Buddhist orders young. He studied Zen at Kennin-ji and Myōshin-ji in Kyoto and took the name Sengaku Shōhō.

At the time, for a warrior-house son to become a monk was a common path for a lower-ranked child of low succession standing.

Shōhō too was not in a position to inherit the house and was expected to walk the life of a scholar-monk.

His meeting with his master, the Rinzai monk Taigen Sessai, would greatly shape the later fate of Yoshimoto.

With Ujiteru's sudden death, the headship was contested between Shōhō and another brother, Genkō Etan.

Etan raised troops backed by the support of the Fukushima clan on his mother's side and fought Shōhō's side across Suruga.

Shōhō gained the upper hand with the aid of his master Taigen Sessai and the political power of his mother Jukei-ni.

In 1536, Etan held out at Hanakura Castle (present-day Fujieda City, Shizuoka Prefecture) but was defeated and took his own life.

This civil war is called the Hanakura Rebellion.

The victorious Shōhō returned to lay life and, receiving a character of his name from the shōgun Ashikaga Yoshiharu, took the name Imagawa Yoshimoto.

It was a transformation from Zen monk to Sengoku daimyō. Yoshimoto employed Sessai as strategist and administrator and set in place the framework for the later expansion of his domain into Suruga, Tōtōmi, and Mikawa.

The learning and political sense he had cultivated in Buddhist orders became the foundation that produced the Tōkai overlord later called 'the finest bowman of the coastal road.

' The young head's decision, having mastered the succession dispute, opened the golden age of the Imagawa house.