Tang Dynasty Emperor Li Yu

Why did Li Yu of the Tang Dynasty posthumously call his younger brother Li Yu, who died young, as Emperor Chengtian? Why?
Tang Dynasty Emperor Li Yu
05-18
#Historical Review##Tang Dynasty#The following is a brief introduction to the reign of the emperors of the Tang Dynasty and their main contributions: 1. Tang Gaozu Li Yuan (618-626): Establishment of the Tang Dynasty, unification
Tang Taizong Li Shimin Tang Xuanzong Li Longji Tang mourning emperor Li Qi Tang Dynasty Emperor Li Yu Tang Dezong Li Shi Tang Gaozong Li Zhi Tang Gaozu Li Yuan Tang Jingzong Li Zhan Tang Muzong Li Heng Tang Ruizong Li Dan
10-11
Why was Tubo, who was in the inferior position in the Tang-Bo War, suddenly attack Chang'an? There are two reasons for this
Tibetan sian Tang Dynasty Emperor Li Yu Tang dynasty Guo Ziyi Cheng Yuanzhen
01-06