Chukai Shonin was born in 1697 and he grew up in Toriyamachi, Tsuruoka. He was born into the samurai caste as well as his uncle's life. He considered his uncle a Living Buddha, and would often pray in front of his uncle's mummified body at a temple. Due due this influence, he decided he wanted to be mummified. Before dying, Chukai traveled to Sakata to restore a temple known as Gyonindera. After the restoration of the historical site, it was known as Kaikoji which still exists today.
Chukai began training required to prepare for mummification. The site chosen for his burial is unknown. Some sources state that it was within the Swamp of Wizards, while others state that he was buried within the precincts of Kaikoji.
Chukai died at the age of 58. The mummified remains of both Chukai and Enmyokai, located at Kaiko Temple in Sakata, Yamagata Prefecture.