Chongzhen

The Grand Secretariat proposed four era names—"Qiansheng" (乾聖), "Xingfu" (興福), "Xianjia" (咸嘉), and "Chongzhen" (崇貞)—for Zhu Youjian to choose from.

[1] Another account states that the four proposed era names were "Yongchang" (永昌), "Shaoqing" (紹慶), "Xianning" (咸寧) and "Chongzhen" (崇貞), and Zhu Youjian chose "Chongzhen" and changed the character "貞" to "禎".

In February 1644 (Chongzhen 17, 2nd month), Li Zicheng established the Shun dynasty in Xi'an, Shaanxi, with the era name "Yongchang" (永昌).

On 25 April 1644 (19th day of the 3rd month), the Shun army captured Beijing, the capital of the Ming dynasty.

After hearing the news, Zhu Yousong, Prince of Fu, ascended the throne in Nanjing, the temporary capital, on 19 June of the same year (15th day of the 5th month), as the Hongguang Emperor, and established the Southern Ming regime.