When the warlord Dong Zhuo hijacked and controlled the Han central government between 189 and 192, Xun You plotted with four others to assassinate him but was discovered and imprisoned.

Following his release after Dong Zhuo's death, he wanted to serve as the Administrator of Shu Commandery (around present-day Chengdu, Sichuan) but eventually settled as an official in Jing Province.

[4][5] The authoritative historical source on Xun You's life is his official biography in book 10 of the Records of the Three Kingdoms (Sanguozhi), which was written by Chen Shou in the third century.

In the fifth century, Pei Songzhi annotated the Sanguozhi by incorporating information from other sources to Chen Shou's original work and adding his personal commentary.

[Sanguozhi 1] His grandfather, Xun Tan (荀曇), whose courtesy name was Yuanzhi (元智), served as the Administrator (太守) of Guangling Commandery (廣陵郡; around present-day Huai'an, Jiangsu).

When his grandfather died, a minor administrative assistant, Zhang Quan (張權), offered to be the tomb keeper.

[Sanguozhi zhu 4] When He Jin rose to power in 189 and became regent to his nephew, the young Emperor Shao, he recruited over 20 notable members of scholar-gentry background to join him including Xun You, who had been noted by the famed judge of talent Yin Xiu (陰脩).

[6] He was appointed as a Gentleman of the Yellow Gate (黃門侍郎), allowing him to act as a liaison to the palace,[7] in the imperial capital, Luoyang and would be the person fellow recruit Zheng Tai would complain to .

The warlord Dong Zhuo took advantage of the ensuing political turmoil to hijack and control the central government.

In Chang'an, Xun You secretly plotted with Zheng Tai (鄭泰), He Yong, Chong Ji (种輯) and Wu Qiong (伍瓊) to assassinate Dong Zhuo, who was notorious for his cruelty and tyranny.

[Sanguozhi 4] However, the Wei Shu mentioned that Xun You was released after he sent someone to persuade and convince Dong Zhuo to free him.

[Sanguozhi zhu 5] Xun You then resigned amidst the chaos resulting from Dong Zhuo's assassination and fled home.

Appointed to be the Chancellor (相) of Rencheng State (任城; southwest of present-day Zoucheng, Shandong), he rejected this appointment and asked to be the Administrator (太守) of Shu Commandery (蜀郡; around present-day Chengdu, Sichuan) because he heard that Shu Commandery was prosperous and situated in a geographically strategic location.

Xun You was then appointed as the Administrator (太守) of Runan Commandery (汝南郡; around present-day Gushi County, Henan) and later, probably in 198,[Sanguozhi 6] summoned to the capital to serve as a Master of Writing (尚書).

Some warned against moving east as Zhang Xiu and Liu Biao might attack after their recent victory.

[16] The defenders became demoralized, there would be a mutiny with the city gates opened, Lü Bu surrendered and was executed.

At the Battle of Boma, Xun You suggested that Cao Cao use a diversionary tactic to eliminate Yuan Shao's general Yan Liang; faking to march across Yan Crossing at the Yellow River as if to attack Yuan Shao's rear then lead lightly armoured troops to Boma.

Seeing the tide had turned, Zhang He and Gao Lan, destroyed their own camps and sought to surrender.

Yuan Shao had treated his subordinates generously and hoped that his sons would cooperate harmoniously to safeguard his territories; that was why turmoil in the Empire never seemed to end.

[Sanguozhi 13] After pacifying Ji Province, Cao Cao wrote a memorial to Emperor Xian to recommend him to award Xun You a marquis title to honour him for his contributions, noting "Master of the Army Xún Yōu from the beginning was a great assistant and minister.

He told Xun You, "Now that the Empire has basically been pacified, it's time for me to share the rewards with virtuous scholar-officials like you.

In the past, Emperor Gaozu allowed Zhang Zifang to choose 30,000 taxable households to form his own marquisate.

Xun You replied, "Since Zuozhi has come on behalf of Yuan Tan to surrender, it's expected that the Imperial Army will go there to pacify the area.

He also said, "Xun Gongda is truly a virtuous man; he fits the saying '(he is) benign, upright, courteous, temperate, and complaisant and thus he gets what he desires.

Lord Prefect Xun is benevolent and virtuous, he displays wisdom in recommending talents, his personal conduct is flawless, and he is capable of adapting his strategies to suit changes.

Meng Ke once said, 'It is a rule that a true royal sovereign should arise in the course of five hundred years, and that during that time there should be men illustrious in their generation.

[Sanguozhi 21] Howard Goodman explains this was partly to provoke his brothers on factional lines, with Can married into the Cao family and other members of the Xun clan leaning towards the Sima family, and partly a philosophical position where Xun You seemed like a good mode for a mystery adapt, above the norms of society and politics.

[29] On the other hand, Pei Songzhi felt Xun You's moral character was far superior to Jia Xu and so they should not have been placed together by Chen Shou.

The second, Xun Shi (荀適), inherited his father's title "Marquis of Lingshu Village" (陵樹亭侯) and had no son to succeed him when he died.

The fleet would be burnt via the false defection of Huang Gai and the incorrect information provided by Xun You's recommended spies.