Biography
Succession and Gao Support
Duan Zhengxing was a son of Duan Zhengyan. In 1147 (17th year of the Shaoxing era, Southern Song) his father abdicated because of rivalry among his sons and external resistance, and Duan Zhengxing succeeded with the support of Gao Liangcheng. The introduction of one account dates his reign from 1148, while its information card and main text start from 1147; another account likewise gives accession in 1147 and a change of era name to Yongzhen the following year, so the entry treats 1147 as the year of accession and 1148 as the year of the era change.
The Period of Gao Family Rule
In 1150 (20th year of the Shaoxing era, Southern Song) Gao Liangcheng led troops to suppress resistance at Tengyue, Yongchang and among the thirty-seven tribes. Both sources attribute the action to the Gao family, and it cannot be written as a personal campaign by Duan Zhengxing. In the same year Gao Liangcheng retired to Chuxiong and his nephew Gao Shouzhen succeeded him as chancellor. In 1163 (1st year of the Longxing era, Southern Song) Gao Shouzhen died and his son Gao Shouchang took charge of state affairs. The power of the Gao chancellors at the Dali court was passed on continuously through Duan Zhengxing's reign.
Abdication and an Inscribed Image
The main text of another account records that in 1172 (8th year of the Qiandao era, Southern Song) Duan Zhengxing abdicated in favour of his son Duan Zhixing and became a monk, while a further account places the abdication in 1171 with 1172 noted as a variant. Another account also presents the inscription on a Buddhist image made for the crown princes Duan Yichangsheng and Duan Yichangxing, which is used to explain the designation "Duan Yichang" and the father-son relation; the dating and interpretation of that inscription are stated only as the source gives them, and no birth or death years are inferred for the two sons.
Era Names, an Inscribed Image and Posthumous Titles
Duan Zhengxing used five era names in succession: Yongzhen, Dabao (also written Taibao or Tianbao), Longxing, Shengming and Jiande. The two sources agree broadly that Yongzhen began in 1148, that Dabao ran from 1149 to 1156, Longxing from 1157 to 1161, Shengming from 1162 to 1163 and Jiande from 1164 to 1171, though individual dates differ by a year or two and no exact date of a particular measure should be calculated from them. Duan Zhengxing was also known as Duan Yichang, "Yichang" being his Buddhist name, that of the bodhisattva Yichang Guanyin; his sons carried the name on as Duan Yichangsheng and Duan Yichangxing. He had a Buddhist image made for the two princes, whose inscription describes "the emperor, the faithful Duan Zhengxing", dedicating the merit to the crown princes Duan Yichangsheng and Duan Yichangxing and praying that their descendants enjoy unending emoluments. The dating and interpretation of the inscription are given only as the source states them, and no birth or death years are inferred for the two princes.
Later genealogical works place him as the third ruler of the later Dali kingdom and the seventeenth ruler of Dali, with the temple name Jingzong and the posthumous title Zhengkang. He posthumously honoured his mother as retired empress; later writers suggest she may have been Consort Wang De, but the standard sources give no clear name, and such conjectures should not be treated as settled fact. After the abdication of his father Duan Zhengyan, the fortunes of Dali declined and the chancellorship remained in the hands of the Gao family.