Emperor Kōtoku was the 36th emperor of Japan, according to the traditional order of succession.
Emperor Kotoku
Memorial Shinto shrine and mausoleum honoring Emperor Kōtoku
The Japanese era name or nengō, is the first of the two elements that identify years in the Japanese era calendar scheme. The second element is a number which indicates the year number within the era,
Emperor Kōtoku
…Nakatomi Kamako (中臣鎌子) (Fujiwara no Kamatari, 藤原鎌足) (614–669), 645–669. The years of Kōtoku's reign are more specifically identified by more than one era name or nengō. Taika (645–650…
Keizō Obuchi, Chief Cabinet Secretary, announces the name of the new era "Heisei" (平成), on 7 January 1989.
Yoshihide Suga, Chief Cabinet Secretary, announces the name of the new era "Reiwa" (令和) at the Prime Minister's Official Residence, on 1 April 2019.
1729 Japanese calendar, which used the Jōkyō calendar procedure, published by Ise Grand Shrine