259 years ago today, on April 16, 1766 (March 8, 1766 lunar calendar), the fifth son of Emperor Qianlong, Aixinjiuluo Yongqi, passed away. Aixinjiuluo Yongqi (March 23, 1741 - April 16, 1766), the word Yunting, a layman named Fujiqin, the fifth son of Emperor Qianlong, and his mother, Yugui Concubine Kerriyet. Yongqi was born on the seventh day of February in the sixth year of Qianlong. He was diligent and studious since childhood. He was the first among the princes to go to the study every day. He had a deep relationship with his fifteenth brother, Yuyan (that is, Emperor Jiaqing). Yongqi is versatile, not only proficient in Manchu and Mongolian languages, but also familiar with astronomy, geography, calendar calculation, especially good at astronomical algorithms. The eight-line method hand scroll he wrote is the most precise, and there is "Banana Tong" manuscript handed down. This algorithm has hundreds of millions of descendants, and then passed on to Sun Yihui, who wrote "This Form" to record its outline. He can also draw poetry. Calligraphy is as famous as the eleventh brother Yongxun, and he is also good at riding horses and archery. Emperor Qianlong was satisfied with his ten-minute love. In addition, on the fifth day of May in Qianlong's 28th year, the Jiuzhou Qing Banquet Hall in Yuanmingyuan caught fire, and Yongqi personally carried his father out of danger. The emperor was very pleased, so in November of Qianlong's 30th year (1765), he was named Prince Rong in Yongqi's disease, becoming the first of the princes to be named king, and the title was "Rong", which also shows the deep love and hope of Qianlong for him. On the eighth day of March the following year, Yongqi, who had suffered from bone tuberculosis for many months, passed away. His posthumous name was "pure" like his imperial father, and this name was also the watch of his life. In the Qing Dynasty, where children were valued by mothers, there was a mother of low status, but she was able to be named a prince and wanted to be established as a reserve, which can show that Emperor Qianlong's love for Yongqi came from himself, unlike the second son Yonglian and the seventh son Yongcong because his mother was Empress Xiaoxian. From this point of view, Yongqi is indeed an excellent prince, and at the same time, she is also a qualified heir in Qianlong's eyes. Concubine Yu was favored because Qianlong loved her son very much. Yongqi performed well and was originally the best choice for the crown prince, but unfortunately his life was only in a hurry for 25 years. When Emperor Qianlong received the British envoy Macartney in the fifty-eighth year of Qianlong (1793), he said to him: "At that time, I regarded the five sons of the emperor as more valuable among the sons, and the Chinese, Manchu, Mongolian, horse steps, shooting and arithmetic were all learned, and they were quite attached to him, and they made it clear that they died due to repeated diseases." Qianlong not only did not avoid the suspicion that the reserve belonged to Yi Yongqi, but more than 20 years after his death, it was enough to show his love and nostalgia for Yongqi. Prince Rong Yongqi and his descendants were incorporated into the right wing near the red flag, and the clan was divided into the first clan. The Palace of Prince Rong is located on the west side of Taiping Lake in Xuanwumen. According to Zhaolian's "Xiaoting Miscellaneous Records", "this garden is all good, and the garden is also good". The Palace of Prince Rong became the residence of the later Prince of Chun, Yisheng. After Yongqi died, he was buried in the Tomb of Prince An Yonghuang of Dingding, which is located in Erli, Yanggezhuang Village, Bulaotun Town, northeast of Beijing. The king of Xunjun was also buried here, where feng shui is excellent. Because they were buried by Emperor Yong Huang and Crown Prince Da Rei Yongqi of Qianlong, the cemetery is also called "Prince's Tomb". (Due to the construction of Miyun Reservoir in 1958, the "Prince's Tomb" complex has been demolished, and the former cemetery is also buried under the reservoir. Because the tomb was not stolen, after opening the underground palace, a large number of funeral objects were found, and the treasures have now been transferred to the Capital Museum for display. In fact, there are not many historical characters in the play "Huanzhu Gege" in history. Among the many characters: Qianlong, Empress Dowager, Empress, Concubine Ling, Concubine Yu, Fifth Brother, Mianyi, etc., there are only a few starring characters, and Xiaoyanzi, Crape Myrtle, etc. are all fictional characters.