Emperor Montoku was the 55th emperor of Japan, according to the traditional order of succession.
Emperor Montoku
Emperor Ninmyō was the 54th emperor of Japan, according to the traditional order of succession. Ninmyō's reign lasted from 833 to 850, during the Heian period.
Emperor Ninmyō
Fujiwara no Junshi, print by Teisai Hokuba, 1800 and 1805, (Rijksmuseum Amsterdam)