Japanese Emperor Kōkaku abdicates on May 7, 1817, in favor of his son, Emperor Ninkō. This event marked a significant moment in Japanese history, as Kōkaku was the first emperor to remain on the throne past the age of 40 in two centuries.
After abdicating, Kōkaku became a Daijō Tennō (retired emperor) and lived in the Sento Imperial Palace (Sakura Machi Palace) It is widely believed that the abdication was a political move in an age of instability and Kokaku continued to be the power behind the throne until his death in 1840.
