Tenan

Japanese: 天安 - てんあん

The Japanese era name (nengo). It was used from 857 to 859 during the Heian period under Emperor Montoku and Emperor Seiwa . The previous era name was Saikō . The era name was Jogan . The era name was changed on February 21, 857 (Saikō 4). The era name was changed to Shozui, in recognition of the auspicious gift of a tree linked together (a tree linked together , meaning two trees joined together to form one) from Hitachi Province (Ibaraki Prefecture) and a white turtle from Mimasaka Province (northeastern Okayama Prefecture). The source of the era name is unknown. In 857 (Ten'an 1), Fujiwara Yoshifusa was appointed as the first commoner to become Daijō- daijin (Grand Minister of State). The following year, Emperor Montoku passed away and Emperor Seiwa, who was 9 years old, ascended to the throne, with Yoshifusa , his maternal grandfather, as his guardian. ◇Can also be read as "tennan."

Tennan [Tenan]

⇒Tenan

Source: Kodansha Encyclopedia of Japanese Era Names Information

Japanese:

日本の元号（年号）。平安時代の857年から859年まで、文徳(もんとく)天皇、清和(せいわ)天皇の代の元号。前元号は斉衡(さいこう)。次元号は貞観(じょうがん)。857年（斉衡4）2月21日改元。常陸(ひたち)国（茨城県）から木連理(もくれんり)（理連木、2本の木が結びついて1本の木になったもの）、美作(みまさか)国（岡山県東北部）から白亀が献上されたことを祥瑞(しょうずい)として行われた（祥瑞改元）。元号名の出典は不詳。857年（天安1）、藤原良房(よしふさ)が人臣初の太政大臣に任じられた。翌年に文徳天皇が崩御し9歳の清和天皇が即位、外祖父の良房が後見に就いた。◇「てんなん」とも読む。