Ten'an (天安) was a Japanese era name (年号,, nengō,, lit. "year name") after Saikō and before Jōgan. This period started in February 857 and ended in April 859.[1] During this time, the emperors were Montoku-tennō (文徳天皇) and Seiwa-tennō (清和天皇).[2]
Events of the Ten'an era
27 September 858 (Ten'an 2, 27th day of the 8th month): Emperor Montoku dies; and the succession (senso) was received by his eldest son. Emperor Seiwa accepted the monarch's role and duties and powers (sokui).[3] This was confirmed in ceremonies.[4] The start of Seiwa's reign was announced at the Ise Shrine (Kotai-jingu) at Ise and at all the tombs of the imperial family.[3]
15 December 858 (Ten'an 2, 7th day of the 11th month): The emperor's grandfather is named regent (sesshō).[3]
♯The Northern pretenders did not recognize the Genkō era. Gentoku was used in the Northern Court until 1332. ₪The Shōkyō era was recognized only by the Northern pretenders, not by the Southern Court. ‡ Upon reunification of the Northern and Southern Courts in 1392, Genchū was discontinued. Meitoku was used until 1394.