It is said that the origin of Toshoji(東昌寺) starts from Toshoji（東勝寺）which was the Hojo regency’s family temple at Nishigaya in Kamakura. Toshoji(東勝寺) was called Seiryuzan Toshoji at that time.

On the other hand, Amitabha hall was built at Ohamitagaya (behind of Prefectural　Zushi　high school ) in Ikego in 1221 in　which　Joroku Amitabaha Nyorai was deified. According to tradition, Minamoto Sanetomo’s mother, Masako, felt sorry for Sanetomo’s unnatural death and she had Unkei cave the image of Joroku Amitabha in order to mourn for his death.

A battalion led by Nitta Yoshisada attached Kamakura from Inamuragasaki on May 22nd, 1333(genko 3). Although Hojo Troops defended desperately, Nitta troops were approaching at Wakamiyaohji. Hojo Takatoki troops entrenched themselves in Toshoji（東勝寺）　with his family and followers. Then Takatoki chose Toshoji as the place to die, where his family tomb was placed. They laid down their lives setting fire to the temple. This　war is known as the battle of Toshoji. It was written　in Taiheiki that 283 people of Hojo family and 830 people of vassals committed　suicide.

Under the fires of war, the chief priest, Shinkai, escaped to Ikego through mountain path carrying the image of Dainichi　Nyorai by himself and he built Toshoji(東勝寺) there. (The image of Dainichi Nyorai was made to mourn for the sprits of the Heike’s dead person under Yoritomo’s orders)

In Tokugawa period, Ikego was governed by Eishouji temple（英勝寺）in 1637 which was the Mito Tokugawa family’s convent temple. The name of Toshoji was changed from Kaishouzan Toshoji to Seiryuzan Toshoji. The Characrer” shou”「勝」 was changed to “shou”「昌」 hesitating that the character of Toshoji includes the same character　as that of Eishoji「英勝寺」. And Amitabha temple and the image of Joroku Amitabha Nyorai were moved to Toshoji by the order of Eishoji.　

Ikego was most developed land in Zushi city from long ago and it had been used as the pass of old Tokaido road and this road was used by Yamato Takerunomikoto to conquer enemies in the east. As　Ikego　had been governed by Mito Tokugawa family, We can see the Mioto Tokugawa family crest (Kamon) everywhere in Ikego such as a portable shrine and lanterns of Shinmeisha shrine.　　

Everything of the temple was destroyed in the fire in 1727 (Kyoho 12). The temple had been rebuilt over 50 years by the chief priests Kanjou, Raiyu and Kaijo. Then today’s Toshoji was completed.

Ancient toshoji in Ikego village