Although there have been many positive evaluations of Li Shimin in later history, it cannot be denied that his throne was not obtained correctly. It was he who launched a coup and seized his brother’s position as crown prince, which led to him obtaining the position of emperor. After this coup, Li Jiancheng and Li Yuanji died. Faced with their surviving wives, Li Shimin married his younger sister Yang, but did not marry his sister-in-law Zheng Guanyin. What is the reason for this?

1. Li Shimin marries his younger sister Yang
In the Xuanwu Gate Incident, Li Shimin killed Crown Prince Li Jiancheng and Prince Qi Li Yuanji, and also killed his 10 nephews in order to eradicate the root of the problem. Princess Zheng Guanyin and Princess Yang of Qi lost their husband and son within a day, losing their reliance and future.
Later, Li Shimin forcibly accepted his beautiful younger sister Yang and gave birth to a son named Li Ming, while Zheng Guanyin, who was both talented and beautiful, died alone. So why didn’t Li Shimin accept Zheng Guanyin?

Is Zheng Guanyin not beautiful enough? No, Zheng Guanyin is both talented and beautiful, dignified and dignified. The epitaph records: “Shuyun Pingting, the night of the bright moon shining on the Milky Way; the graceful delivery of the youth, the gentle breeze spreading the fragrance of peach and plum blossoms.” Any beautiful words about her seem to be an exaggeration.
Why didn’t you marry your sister-in-law
Is Zheng Guanyin much older than Li Shimin? No, Zheng Guanyin was born in 599 AD, the same age or one year younger than Li Shimin.
Is it because the elder sister-in-law is like a mother? No, Zheng Guanyin married into the Li family either in the same year as Empress Changsun or after Empress Changsun. That is to say, Li Shimin, who lost his mother in his early years, did not receive special care from Zheng Guanyin, so he could not cultivate such feelings.
In fact, Li Shimin’s refusal to accept Zheng Guanyin was based on political considerations. And Zheng Guanyin also refused to compromise.
3. Zheng Guanyin
Firstly, Zheng Guanyin’s status as the Crown Princess determines her uniqueness. If it weren’t for Li Shimin’s coup, Li Jiancheng would have been the future emperor of the Tang Dynasty, and Zheng Guanyin would have been the future empress, with the mother of the world. Li Shimin was criticized for killing his brother and forcing his father Li Yuan to step down, which became a stain on his life. He tried his best to downplay this stain and prove that he was forced to do so. How dare he accept the former Crown Princess again? For the rest of his life, he will only keep her under house arrest and provide her with a luxurious life to show his mercy and demonstrate the legitimacy of his accession to the throne.
As the Queen of Qi, even if Li Shimin accepted Yang, he would not receive too much criticism and could instead win over the Yang family behind Yang. But even Yang was not accepted by Li Shimin until many years after the Xuanwu Gate Incident.
Furthermore, there is the Xingyang Zheng family behind Zheng Guanyin. The Zheng family in Xingyang was one of the five noble families and seven nobles at that time. Li Shimin had to be very cautious about how to deal with Zheng Guanyin, otherwise it would hurt the hearts of the aristocratic families, who were extremely concerned about etiquette and morality. The fact that Zheng Guanyin was chosen by Li Yuan as the Crown Princess itself indicates the preciousness of the Crown Princess’s family background. Not to mention whether the Zheng family would agree to such Zheng Guanyin, what position would Li Shimin place if he forcibly accepted her?
Finally, Zheng Guanyin’s family background and former status as a crown princess determine that she can choose her own way to spend the rest of her life. However, she clearly did not want to become Li Shimin’s concubine. The epitaph records Zheng Guanyin as follows: “He was a rare and virtuous woman, devoted solely to ritual education.” This indicates that Zheng Guanyin was a dignified and dignified person who adhered to ritual education. Moreover, her background in Xingyang’s Zheng family determined that she received top-notch education from a young age, and her character was natural. Moreover, even if she did not love Li Jiancheng very much, she had feelings for him. Li Shimin killed her husband and son, and she had no way to seek revenge, but she would never be his woman. Moreover, during the Xuanwu Gate Incident, she was likely pregnant. Although she was a daughter, she was the only comfort for the rest of her life.
After the Xuanwu Gate Incident, she was placed under house arrest in the palace and spent fifty years there. Although she had luxurious clothing and food, she was not her favorite. She was frugal throughout her life and never loved fancy clothes or rouge, only reading. There are many taboos and restrictions on movement in the palace.
In 676, 78 year old Zheng Guanyin passed away inside Changle Gate. Funeral procession in the main residence of the 5th daughter in Guide County.