Also, it has been designated as a nationally Important Cultural Property, as it contains pictures of both Dōsan and Yoshitatsu.

In 1450, Saitō Myōchin served as the guardian of upper Mino Province on behalf of the Toki clan.

(Myōchin was the son of Saitō Sōen, who had earlier served as the guardian of Mino Province.)

Afterwards, as Japan entered the Sengoku period, Nagai Shinzaemon used the area around his temple as his base for uniting the region.

Dōsan, his son, continued his father's base of operations for a second generation, designating Jōzai-ji the family temple.