Hongguang

On 7 June 1644 (Chongzhen 17, 3rd day of the 5th month), Zhu Yousong was proclaimed "regent" (監國) in Nanjing and ascended the throne on 19 June (15th day of the 5th month), taking next year Hongguang 1 (弘光元年, "the first year of Hongguang").

On May 1645 (5th month), the Qing army conquered Nanjing, and Zhu Yousong was captured on 15 June (22nd day of the 5th month).

On 18 August 1645 (27th day of the leap 6th month), the Longwu Emperor ascended to the throne and continued to use it.

The following month, the era was changed to Longwu.

On 24 August (4th day of the 7th month), Zhu Yihai, Prince of Lu, proclaimed himself "regent" and still using the Hongguang era name, and the following year, the era was changed to Jianguo Lu 1 (監國魯元年, "the first year of Jianguo Lu").