Emperor Ai of Tang
In 904, Zhu forced Emperor Zhaozong to move the capital from Chang'an to Luoyang, which was even more firmly under his control. Later that year, fearing that the adult Emperor Zhaozong would try to rise against him while he was away on campaigns against other warlords, he had Emperor Zhaozong assassinated. Bypassing Li Yu and the other older princes, he had an edict issued in Emperor Zhaozong's name creating Li Zuo crown prince and changing his name to Li Chu. Shortly after, Li Chu took the throne (as Emperor Ai). Empress He, who survived the assassination, was honored empress dowager.
Xianbei
In 534, the Northern Wei split into an Eastern Wei (534-550) and a Western Wei (535-556) after an uprising in the steppes of North China inhabited by Xianbei and other nomadic peoples. The former evolved into the Northern Qi (550-577), and the latter into the Northern Zhou (557-581), while the Southern Dynasties were pushed to the south of the Yangtze River. In 581, the Prime Minister of Northern Zhou, Yang Jian, founded the Sui dynasty (581-618). His son, the future Emperor Yang of Sui, annihilated the Southern Chen (557-589), the last kingdom of the Southern Dynasties, thereby unifying northern and southern China. After the Sui came to an end amidst peasant rebellions and renegade troops, his cousin, Li Yuan, founded the Tang dynasty (618-907); Li led China to develop into one of the most prosperous states in history. Sui and Tang dynasties were founded by Han Chinese generals who also served the Northern Wei dynasty. Through these political establishments, the Xianbei who entered China were largely merged with the Han, examples such as the wife of Emperor Gaozu of Tang, Duchess Dou and Emperor Taizong of Tang's (Li Shimin's) wife, Empress Zhangsun, both have Xianbei ancestries, while those who remained behind in the northern grassland emerged as later powers to rule over China.