Overview
Li Zi (李滋) (died 897), formally the Prince of Tong (通王), was an imperial prince of the Chinese Tang Dynasty. He was the favorite son of Emperor Xuānzong, but was unable to take the throne after Emperor Xuānzong's death, as his older brother Li Wen (Emperor Yizong) was chosen by the eunuch Wang Zongshi (王宗實), who overpowered other eunuchs who supported Li Zi. Later, during the reign of Emperor Yizong's son (Li Zi's nephew) Emperor Zhaozong, Emperor Zhaozong tried to commission imperial princes to command armies to counteract the powerful warlords (Jiedushi) and eunuchs. In response, in 897, when Emperor Zhaozong had to flee to the domain of one of the warlords, Han Jian, Han falsely accused 11 imperial princes, including Li Zi, of treason, and massacred them without approval from Emperor Zhaozong.
Background
It is not known when Li Zi was born, but as his oldest brother Li Wen was born in 833, and Li Zi was already born by the time that his father Li Chen became emperor (as Emperor Xuānzong) in 846, he must have been born between those dates. When Emperor Xuānzong became emperor, he created five of his sons imperial princes, including Li Zi, who was created the Prince of Kui. Li Zi was Emperor Xuānzong's third son. His mother's name is lost to history.
Li Zi was said to be Emperor Xuānzong's favorite son, and he lived in the palace with four of his brothers, while Li Wen, then the Prince of Yun, who was not favored, was sent out of the palace to live at the residence of the imperial princes, known as the Sixteen Mansions. Emperor Xuānzong also commissioned the officials Zheng Zhang and Li Ye to attend to Li Zi's studies, lecturing him once every five days.
Failure to succeed to the throne
As Li Zi was Emperor Xuānzong's favorite son, Emperor Xuānzong repeatedly considered creating him crown prince, but as Li Zi was not the oldest son, he hesitated, and went throughout his reign without designating an heir. In 859, when Emperor Xuānzong grew seriously ill due to the side effects of the immortality pills that were given to him by the alchemists Li Xuanbo, Yu Zizhi, and Wang Le, he entrusted Li Zi to three eunuchs that he favored — the directors of palace communications Wang Guizhang and Ma Gongru, and the liaison with imperial officials Wang Jufang.
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