Tenchō
Tenchō (天長?) was a Japanese era name (年号,, nengō,?, lit. "year name") after Kōnin and before Jōwa. This period spanned the years from January 824 through January 834. The reigning emperors were Junna-tennō (淳和天皇?) and Ninmyō-tennō (仁明天皇?).
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