Tenshō (Heian period)Tenshō was a Japanese era name after Daiji and before Chōshō. This period spanned the years from 1131 through 1132. The reigning emperor was Emperor Sutoku of Japan.Change of EraJanuary 31, 1131 Tenshō 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 Daiji 6, on the 29th day of the 1st month of 1131.Events of the ''Tenshō'' Era1131 : The udaijin Fujiwara Yetada was elevated to sadaijin; and the naidaijin Arihito filled that vacancy by becoming udaijin. The dainagon Fujiwara no Munetada was made ''nadaijin.''