For those who are interested in Yang Guifei’s ex husband, the History Encyclopedia editor brings a detailed article for your reference.

Li Mao, the son of Emperor Xuanzong of Tang and the former husband of Yang Guifei, had three stages in his life: a noble birth, a bleak youth, and a good end in his later years.
Shouwang Li Mao, born noble, is the standard master born with a golden key. He was not only the 18th son of Emperor Xuanzong of Tang, Li Longji, but more importantly, his mother was Empress Wu Huifei. Empress Wu Huifei is not an ordinary harem woman. She is the niece of Empress Wu Zetian. Not only is she very beautiful, but she also has a gentle and virtuous personality, with knowledge, culture, and connotation. “Empress Wu Huifei is young but gentle, long and wise, and she follows the rules of etiquette and speaks in accordance with historical records” (Old Book of Tang). Having been exclusively favored by the lustful Li Longji for over a decade, the two have a deep affection for each other. It can be said that Li Longji, for the sake of Empress Wu Huifei, abolished his once deeply emotional wife, Queen Wang, and killed Crown Prince Li Ying, who was “intelligent, studious, and talented”. After the death of Empress Wu Huifei, Li Longji was deeply affected. Due to missing Empress Wu Huifei, he had no interest in women in the imperial harem for a long time.
Having an emperor father and a queen mother who is deeply loved by the emperor and holds the same status as the empress is already extremely fortunate. Li Mao’s good luck is far more than that. His mother Wu Huifei followed Li Longji for more than ten years, but had multiple miscarriages. Although she gave birth to two sons and one daughter, they all died young. Before Li Mao, there were no children who grew up to adulthood. With this layer of tiling and background, Li Mao’s birth is even more dazzling. Emperor Xuanzong of Tang was afraid that Li Mao would also die prematurely like other children, so he sent Li Mao to his brother Li Xian’s Ning Wang Mansion at birth, where he was personally nurtured by the Ning Princess Yuan for more than ten years.

Li Mao became the only son of Li Longji and Empress Wu Huifei, and his nobility and importance can be imagined. In March of the thirteenth year of the Kaiyuan era (725 AD), when Li Mao was seven years old, he was appointed as the Prince of Shou. In the fifteenth year (727 AD), he was appointed as the Governor of Yizhou and the Ambassador of Jiannan Jiedu. In the twenty third year (735 AD), he was promoted to the position of the Chief of Ceremonies and Three Departments. At the age of seventeen, the Prince of Shou, Li Mao, married Yang Yuhuan as the Princess of Shou. The life of Prince Shou Li Mao has been full of ups and downs, soaring forward with great success. If everything goes smoothly, he is the inevitable candidate for the crown prince and will also be the next emperor of the Tang Dynasty. However, things often rise and fall, and Li Mao’s good luck did not last.
Li Mao’s mother, Wu Huifei, passed away in December of the 25th year of the Kaiyuan era (737 AD) at the young age of 39. Li Mao was 19 years old that year. The death of the mother was fatal for Li Mao. During the lifetime of Empress Wu Huifei, she was the only one of her mother and indirectly equivalent to the only one of Emperor Xuanzong of Tang, Li Longji. However, after her mother’s death, she lived in the most ruthless imperial family, and Li Mao’s status plummeted. He was no longer the only one in the eyes of the emperor’s father, but became one of his father’s more than thirty sons.
For Li Mao, what was even more unfortunate was that after his mother passed away, his father took a liking to his wife, Princess Shou, Yang Yuhuan, and forcibly divorced Li Mao from Yang Yuhuan. Then, under the pretext of praying for his mother, Empress Dowager Dou, he sent Yang Yuhuan to the Taoist temple and became Yang Taizhen. In the 29th year of the Kaiyuan era (741 AD), the impatient Li Longji sent someone to bring Yang Taizhen into the palace and called him the Empress. In the fourth year of Tianbao (745 AD), she was officially conferred the title of Imperial Noble Consort, with all treatment and rank equivalent to that of the Empress. The queen, who had won over the country and the city, was forcibly taken away by her father. She couldn’t have any dissatisfaction or grievances, and the frustration and anger in her heart can be imagined.
After his wife was taken away by Emperor Li Longji, Li Mao’s political future was completely ruined. Li Longji, who braved the bloody storm all the way, was already wary of palace coups. Previously, he had unjustly killed three sons in one day just because of a single sentence, which showed his suspicion. Such a father emperor would never appoint a son who harbored hatred for taking his wife as the crown prince. On the contrary, they will only have a strong sense of vigilance towards Li Mao and strengthen their prevention everywhere, seeing him as an alternative.
In his later years, Li Longji may have been moved by the “one-day killing of his son” incident, no longer being cruel and ruthless towards his son, but showing more kindness towards him. So, after Li Mao’s stunning wife Yang Yuhuan was taken away and lived alone for over four years, Li Longji felt a little guilty and chose a new queen for Li Mao. The new queen was the granddaughter of former prime minister Wei Juyuan. Although not as beautiful as Yang Yuhuan, she was kind-hearted, gentle in temperament, and had excellent upbringing. The two supported and loved each other, had children, and lived together for more than thirty years. Li Mao also became indifferent to power from then on, actively distancing himself from the center of power and returning to the position of Shouwang in a peaceful manner. He passed away due to illness in the tenth year of the Dali reign of Emperor Tang (775 AD) at the age of 57, which can be considered a good end.
His former wife Yang Yuhuan, however, fled hastily to Shu with Emperor Xuanzong of Tang, Li Longji, in the fifteenth year of the Tianbao era (756 AD) after the outbreak of the An Lushan Rebellion. While passing through Mawei Post (now west of Xingping City, Shaanxi Province), she mutinied with the imperial guards and killed her cousin, Prime Minister Yang Guozhong, with a chaotic knife. Yang Yuhuan was also forced to be executed, a stunning beauty of a generation whose fragrance faded away.