Ninju

Ninju was a Japanese era name after Kashō and before Saikō. This period spanned the years from April 851 through November 854. The reigning emperor was Emperor Montoku.

Change of era

February 5, 851 Ninju gannen: The new era name was created to mark an event or series of events. The previous era ended and the new one commenced in Kashō 4, on the 28th day of the 4th month of 851.
Events of the ''Ninju'' era
853 : The emperor visited the home of udaijin Fujiwara no Yoshifusa, the grandfather of his designated heir.
853 : Asama Shrine in Suruga Province is styled myōjin, and the shrine is accorded national ranking in the lists of shrines and temples.