In 1590, Ōmandokoro, the mother of Toyotomi Hideyoshi, made a pilgrimage to Seiganji Temple — the same year Hideyoshi completed the unification of Japan. After Hideyoshi's death, the temple burned down in 1600 and was rebuilt by order of his son Toyotomi Hideyori, cementing the temple's lasting ties with the Toyotomi clan.