In ancient China, there was a group called eunuchs, also known as eunuchs. Under normal circumstances, everyone's impression of this group is not very good, because there have been many well-known figures in the history of eunuchs, such as Yan Yi in the Warring States period, Zhao Gao in the Qin Dynasty, Wei Zhongxian in the Ming Dynasty, and so on. In fact, in ancient times, there were also wise people in the eunuch group, but people often ignored them.

There was once such a eunuch, he became the only eunuch emperor in China, although the power of the opposition was highly praised, and his son changed history, this person is Cao Teng. People who know the history of the Three Kingdoms probably know Cao Cao's life, but Cao Teng, the first founder of the Cao clan, is always unknown.
The Chronicle of the Three Kingdoms records that Cao Teng was a descendant of the han dynasty name Cao Shan, born in 100 AD. But I don't know why, Cao Teng was only 6 years old when he became a eunuch, and entered the palace to serve Liu Bao, the Hanshun Emperor at the time, as his "companion". Cao Teng has been old and heavy since he was a child, and Empress Deng and Liu Bao both like him.
When Emperor Hanshun ascended the throne, Cao Teng became Xiaohuangmen and Zhongchang. After Cao Teng waited in the palace without waves for 19 years, Emperor Han Shun died, and the successor Emperor Han Chong was only 2 years old, still a child who did not understand anything, and he had bad luck, and he died in less than half a year, and the imperial court was in chaos, and the ministers quarreled and discussed who would be the emperor.
Emperor Shun of Han's brother-in-law Liang Ji (梁冀) took sole power, and in 145 AD, he installed the 8-year-old Emperor Han. As a result, Emperor Han was poisoned by Liang Ji a year after he ascended the throne, and the throne was once again suspended. In this case, Cao Teng took the initiative to find Liang Ji and analyze for him who should be made emperor. Under the influence of Cao Teng, Liang Ji abandoned the King of Qinghe and established Liu Zhi as emperor, which was the historical Emperor Huan of Han.
In this way, Cao Teng became a meritorious minister, was named the Marquis of Feiting, promoted to the position of Grand Changqiu, and was deeply trusted by the emperor. Ordinary people may feel that cao Teng has such a status, and he will probably get carried away and make a fool of himself. But the fact was unexpected, Cao Teng not only did not cause trouble, but often recommended sages to the emperor, Nanyang Zhang Wen, Hongnong Zhang Yi, all of which were recommended by Cao Teng.
Cao Teng had a rival to the Wu clan and also raised a son, Cao Song, who indirectly changed history because he gave birth to a son, Cao Cao. Regarding the blood relationship between the three generations of the Cao family, there has been a debate, after modern scientific research and genetic comparison, Cao Song, Cao Cao father and son are indeed not the descendants of Cao Gan, but Cao Song is not from the Xiahou clan, experts infer that Cao Song may come from Cao Teng's own clan.
But no matter what, Cao Cao's origin still made him despised by many people, in that era of paying attention to the door, Yuan Shao asked Chen Lin to write "Yu Zhou Wen for Yuan Shao" to denounce Cao Cao, and he despised Cao Cao's ancestors, calling Cao Cao "ugly and ugly, originally without Yi Virtue"; Sima Yi, who was born in a family family, also because of Cao Cao's bad birth, initially killed and did not want to do things for him.
However, Cao Cao still became the most powerful prince at the end of the Eastern Han Dynasty, after all, because of Cao Teng's relationship, Cao Cao's father Cao Song had once been an official to the rank of Taiwei (the head of the Three Dukes), and Cao Cao's lineage was not carefully investigated. Later, when the State of Wei was established, the Wei Ming Emperor Cao Rui posthumously named Cao Teng emperor Gao, and Cao Teng completed a magnificent reversal from eunuch to emperor, leaving a name in Qingshi!