Hōjō Sadatoki

Hōjō Sadatoki (北条 貞時) was the ninth shikken (regent) of the Kamakura shogunate (reigned 1284 - 1301), and Tokuso (de facto ruler of Japan) from his appointment as regent until his death.

Born to the regent Tokimune and his wife from the Adachi family, Sadatoki became a shikken at age 14 upon the death of his father. Sadatoki was under the guardianship of Taira Yoritsuna.

Shimotsuki Incident
The Hōjō clan had variously defeated many rival families, leaving only the Adachi clan, with whom the Hōjōs were allies. However, a plot by Adachi Yasumori to usurp the Hōjō resulted in Sadatoki authorizing Taira Yoritsuna to attack the Adachi. It is possible Taira Yoritsuna may have falsified the charges against Yasumori due to political rivalry.

The attack occurred in November 1285 and is known as the Shimotsuki (Frosty Moon) Incident. It was fought near the Adachi residence, and the Adachi were caught unaware. The fighting lasted five hours and Yasumori was forced to commit suicide, along with his family and many supporters. Over 500 died in all and the Adachi family was almost exterminated. Adachi Yasumori was Sadatoki's father's brother-in-law.

Heizen Gate Incident
Sadatoki's soldiers killed Taira Yoritsuna and 90 of his followers in the Heizen Gate Incident (平禅門の乱, Heizenmon no Ran) in 1293. He did this purge in confusion after the 1293 Kamakura earthquake.

Regency ends and death
Sadatoki ended his regency and entered the priesthood in 1301. Some sources claim that, although secluded in a temple, he continued to administer Japan until his death in 1311. He is enshrined with his father and Hōjō Takatoki.

A mass requiem commemorating the 12th anniversary of Sadatoki's death took place at Engakuji in 1323. Jufukuji temple sent 260 priests.