In 1637, Itakura Shigemasa was dispatched as a tsuitoshi (search-and-kill commander) to quash the Shimabara-Amakusa Rebellion, and he was killed in battle on New Year’s Day of 1638. Later, his grave was built on the precincts of Kotoji Temple in Imamuramyo. However, after the Catastrophe in Shimabara of 1792, his grave went missing. At the time of the kaechi (exchange of land) of Kotoji Temple in 1817, his gravestone was re-erected. However, the lost gravestone was found when a well was being dug in the castle town. So, there are now two gravestones—old and new—for honoring Itakura Shigemasa, both of which have been designated as historical sites by Shimabara City.