According to the Azuma Kagami, when Suketsune had his coming-of-age ceremony (genpuku), his father promised that Suketsune would marry Mangō Gozen, the daughter of Itō Sukechika, and Sukechika would become Suketsune's guardian.[2] However, Sukechika did not accept the fact that Suketsune, who was not the eldest son, would inherit the manor, and invaded Suketsune's territory following his father's death.[3] Sukechika also made Mangō Gozen divorce Suketsune.[4][5]
Suketsune was deeply angered over these events and ordered the assassination of Sukechika. In October 1176, a group of thugs attacked Sukechika, who was hunting in Okuno, Izu Province with his son Kawazu Sukeyasu. The arrow shot at Sukechika missed, and hit Sukeyasu instead, killing him.[5]
In 1193, Suketsune participated in shogunMinamoto no Yoritomo's large-scale hunting event, the Fuji no Makigari, at the foot of Mount Fuji. At midnight on June 28, the final day of the hunting event, two brothers, Soga Sukenari and Tokimune, broke into the building where Suketsune and two prostitutes were resting. The two brothers killed Suketsune to avenge their father's death. Ōtōnai, a shinkanofKibitsu ShrineinBizen Province, was also killed in the incident. Sukenari was then killed by Suketsune's retainer Nitta Tadatsune. Tokimune attempted to assassinate the shogun, but was captured by Gosho no Gorōmaru. After the turmoil, Yoritomo questioned Soga Tokimune and considered saving his life, but Suketsune's son Inubusamaru (later Itō Suketoki) cried pleading for justice, and Yoritomo changed his mind and had Tokimune executed.[6][7] This incident came to be known as the Revenge of the Soga Brothers.[4]