Emperor Ninmyō

was the 54th emperor of Japan, according to the traditional order of succession. His reign started in 833 and ended in 850.
Traditional history.
Before he became the monarch, this prince's personal name ("imina") was . 
Ninmyō was the second son of Emperor Saga and the Empress Tachibana no Kachiko. 
Ninmyō had nine Empresses, Imperial consorts, and concubines ("kōi"); and he had 24 Imperial sons and daughters.
Events of Ninmyō's life.
Ninmyō was Crown Prince for 10 years.
After his death.
Emperor Ninmyō is traditionally venerated at his tomb; the Imperial Household Agency designates , in Fushimi-ku, Kyoto, as the location of Ninmyō's mausoleum.
Ninmyō was sometimes posthumously referred to as "the Emperor of Fukakusa," because that was the location of his tomb.
Eras of reign.
The years of Ninmyō's reign are identified by more than one era name ("nengō").