Yang Nandang 楊難當

Yang Nandang 楊難當 (r. 436-442) was the sovereign of the dominion of Later Qiuchi 後仇池 (385-443/473).

He hailed from Qingshui 清水 in the commandery of Lüeyang 略陽 (in today's Gansu province) and belonged to the people of the Di 氐. Even if the dominion of Qiuchi was autonomous, its rulers were formally invested by the Liu-Song dynasty 劉宋 (420-479). Yang Nandang was given the title of General Commanding the Troops (guanjun jiangjun 冠軍將軍).

In 429, his older brother Yang Xuan 楊玄 died, Nandang supported his nephew Yang Baozong 楊保宗 to inherit the throne, but soon thereafter, he deposed Baozong and ruled himself, adopting the titles of Area Commander-in-chief (dudu 都督) of the provinces of Yongzhou 雍州 and Liangzhou 涼州, regional inspector (cishi 刺史) of Qinzhou 秦州, Commander Pacifying the Qiang tribes (pingqiang xiaowei 平羌校尉), and King of Wudu 武都. However, the accepted the suzerainty of the Song dynasty, which confirmed his titles in 430. In 432, Yang also took the title of General Conquering the West (zhengxi jiangjun 征西將軍). A year later, he accepted the suzerainty of the Northern Wei empire 北魏 (386-534) as well, which made him General Conquering the South (zhengnan jiangjun 征南將軍) and King of Southern Qin 南秦.

Taking advantage of the fact that Liu Daoji 劉道濟 (d. 437), the regional inspector of Yizhou 益州 (approx. Sichuan), had lost the support of the people, he sent the leader of an uprising of landless people, Sima Feilong 司馬飛龍 (Cheng Daoyang 程道養, r. 432-437) to lead a revolt into Shu. He also exploited the opportunity created by the misrule of Zhen Fahuo 甄法護 (d. 433), the regional inspector of Liangzhou 梁州, and the fact that his successor, Xiao Sihua 蕭思話（406-455), had not yet taken office. Yang attacked Liangzhou, captured Baima 白馬, and occupied the Hanzhong region 漢中. The following year, he was defeated by Xiao Sihua, retreated from Hanzhong, and sent an envoy to present a memorial to apologise for his crimes.

However, in 436, he declared himself King of Great Qin 大秦 and adopted the reign motto Jianyi 建義. He established a queen and crown prince, appointed officials in imitation of an imperial court, yet continued to acknowledge vassal status to both the Song and Wei empires. In 440, after a severe drought and multiple disasters in Qiuchi, he resumed the former, legal title of King of Wudu. The following year, he launched a full-scale southern campaign to seize the Sichuan region, dispatching Fu Chong 苻沖, General Establishing Loyalty (jianzhong jiangjun 建忠將軍), to advance eastward to Luoyang 洛陽 in order to block the Liangzhou army. He captured Jiameng 葭萌 (close to modern-day Guangyuan 廣元, Sichuan), seized Shen Tan 申坦, the governor (taishou 太守) of Jinshou 晉壽, and advanced to besiege Fucheng 涪城 (close to Mianyang 綿陽, Sichuan).

In 422, Qiuchi suffered successive attacks from the Song army, resulting in the loss of Wuxing 武興, Xiabian 下辨, and Baishui. Yang Nandang fled to Shanggui 上邽 (modern-day Tianshui 天水, Gansu) and was shortly later received by Emperor Taiwu 北魏太武帝 (r. 423-451) at the northern palace in Shuo 朔北行宮. During the reign of Emperor Wencheng 北魏文成帝 (r. 452-465), he was appointed regional inspector of Yingzhou 營州 and later served as a high-ranking official in the outer capital. His posthumous title was King Zhong 武都忠王.