Hongwu

Hongwu (23 January 1368 – 5 February 1399) was the era name of the Hongwu Emperor during his reign, and was also the Ming dynasty's first era name.

On 23 January 1368 (Wuyuan 2, 4th day of the 1st month), Zhu Yuanzhang proclaimed himself emperor of the Ming dynasty in Yingtian Prefecture with the era name "Hongwu".[1] During the Hongwu period, there was no war in the country, and the society quickly recovered from the war in the late Yuan dynasty. The population increased rapidly, and the economy developed rapidly. It was known in historiography as the "Reign of Hongwu" (洪武之治).

The emperors only used one era name during their reigns since the Hongwu Emperor began to form a practise (Emperor Yingzong of Ming had two era names because of his abdication and later restoration, and the rest used one era name). It was known as the yī shì yī yuán zhì (一世一元制; lit. "one-era-name-for-a-lifetime system").

On 24 June 1398 (Hongwu 31, 10th day of the 5th leap month), the Hongwu Emperor died. On 30 June (16th day of the 5th leap month), Imperial Grandson-heir Zhu Yunwen ascended to the throne as the Jianwen Emperor. The following year, the era was changed to Jianwen.[2][3]

On 18 July 1402 (Jianwen 4, 18th day of the 6th month), the Yongle Emperor, who usurped the throne through the Jingnan campaign, abolished the Jianwen era name and renamed it "Hongwu 35" (洪武三十五年, "the thirty-fifth year of Hongwu"). The following year, the era was changed to Yongle.[2][4] According to Xia Xie (夏燮)'s Ming Tongjian (明通鑑), since Zhu Di started his rebellion at Beijing in 1399 (Jianwen 1), he began restoring the Hongwu era name in his conquest areas, and after the Jingnan campaign, he ordered the whole country to reuse the Hongwu era name.[5]