Chinese era name
The first monarch to adopt era names was the Emperor Wu of Han in 140 BCE,[1][2] and this system remained the official method of year identification and numbering until the establishment of the Republic of China in 1912 CE, when the era name system was superseded by the Republic of China calendar.[2][3][4] Chinese era names were titles adopted for the purpose of identifying and numbering years in Imperial China.Era names originated as mottos or slogans chosen by the reigning monarch and usually reflected the political, economic and/or social landscapes at the time.The process of declaring an era name was referred to in traditional Chinese historical texts as jiànyuán (建元).For example, when referencing the year 410 CE, Chinese sources could either render it as Běi Yān Tàipíng èr nián (北燕太平二年; lit."second year of Taiping of the Northern Yan") or Běi Yān Wéngchéng Dì Tàipíng èr nián (北燕文成帝太平二年; lit."Heaven-bestowed ritualistic richness, nationally celebrated") of the Western Xia are examples of Chinese era names that bore more than two characters.[5][6] For example, Korean regimes such as Silla, Goryeo, and Joseon at various times formally adopted the era names of the Tang, Wu Zhou, Later Liang, Later Tang, Later Jin, Later Han, Later Zhou, Northern Song, Liao, Jin, Yuan, Northern Yuan, Ming, and Qing dynasties of China for both domestic and diplomatic purposes.[1][2] Prior to the introduction of the first era name in 140 BCE, Chinese monarchs utilized the Qianyuan (前元), Zhongyuan (中元) and Houyuan (後元) systems to identify and number years.The Hongwu Emperor started the tradition of having only one era name for one monarch—known as the yí shì yì yuán zhì (一世一元制; lit.Furthermore, in Japan, in theory it is difficult to mention future dates since it is sometimes hard to tell whether the current emperor will live long enough for its citizens to use that era name.