Xun You (157–September 214), courtesy name Gongda, was a statesman who lived during the late Eastern Han dynasty of China and served as an adviser to the warlord Cao Cao. Born in the influential Xun family of Yingchuan Commandery (around present-day Xuchang, Henan), Xun You was recruited into the civil service by the general He Jin. 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.
In 196, after Cao Cao received the figurehead Han sovereign, Emperor Xian, and reestablished the new imperial capital in Xu (許; present-day Xuchang, Henan), he summoned Xun You to the capital to serve as a Master of Writing and Military Adviser. From then on, Xun You was simultaneously a Han statesman and a subordinate of Cao Cao. He accompanied Cao Cao on his military campaigns as a tactical adviser and occasional commander. Between 198 and 207, he advised Cao Cao in the battles against rival warlords such as Zhang Xiu, Lü Bu, Yuan Shao and Yuan Shao's successors. In 207, on Cao Cao's recommendation, Emperor Xian made Xun You a village marquis to honour him for his contributions. In 213, after Cao Cao had been enfeoffed by Emperor Xian as the Duke of Wei, Xun You served as the Prefect of the Masters of Writing in Cao Cao's dukedom. In 214, while accompanying Cao Cao on a campaign against the southern warlord Sun Quan, Xun You died of illness along the way. The Sanguozhi describes Xun You as a deep and perceptive thinker who kept a low profile and guarded confidential matters.Sanguozhi vol.10.
Historical sources 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. Some alternative texts used in the annotations to the Sanguozhi include: the Wei Shu (魏書; Book of Wei), by Wang Shen (), Xun Yi () and Ruan Ji; the Xun Shi Jia Zhuan (荀氏家傳; Xun Family Genealogy); the Han Ji (漢紀; Annals of Han), by Zhang Fan (); the Fu Zi (), by Fu Xuan.
Family background and childhood Xun You was born in the influential Xun family, whose ancestral home was in Yingyin County (), Yingchuan Commandery (), which is in present-day Xuchang, Henan.(荀彧字文若，潁川潁陰人也。) Sanguozhi vol. 10. His grandfather, Xun Tan (), whose courtesy name was Yuanzhi (),Houhanshu, vol.62 served as the Administrator () of Guangling Commandery (廣陵郡; around present-day Huai'an, Jiangsu).(荀攸字公達，彧從子也。祖父曇，廣陵太守。) Sanguozhi vol. 10. Xun Tan and his brother Xun Yu (荀昱; courtesy name Botiao [伯条]) were deeply against the eunuch faction at court. While they were serving as officials (Tan as Administrator of Guangling and Yu as Chancellor of Pei), whenever they encountered associates or subordinates of the eunuch faction, they would execute such persons even if they were convicted of minor crimes. Later, Xun Yu died together with Li Ying in late 169, while Tan was barred from office as a partisan for the rest of his life.(淑兄子昱字伯条，昙字元智。昱为沛相，昙为广陵太守。兄弟皆正身疾恶，志除阉宦。其支党宾客有在二郡者，纤罪必诛。昱后共大将军窦武谋诛中官，与李膺俱死。昙亦禁锢终身。) Houhanshu, vol.62 Xun You's father, Xun Yi (), served as a commandery-level Assistant Officer (). Xun Yi was a second cousin of Xun Yu and Xun Yue. Hence, Xun You was Xun Yu's and Xun Yue's second cousin-nephew(荀氏家傳曰：曇字元智。兄昱，字伯脩。張璠漢紀稱昱、曇並傑俊有殊才。昱與李膺、王暢、杜密等號為八俊，位至沛相。攸父彝，州從事。彝於彧為從祖兄弟。) Xun Shi Jia Zhuan and Han Ji annotations in Sanguozhi vol. 10. even though he was six years older than Xun Yu.(計其年大彧六歲。) Wei Shu annotation in Sanguozhi vol. 10.
Xun You was orphaned at a young age. He was probably raised by his uncle Xun Qu () and his grandfather Xun Tan. When his grandfather died in 169, a minor administrative assistant, Zhang Quan (), offered to be the tomb keeper. Xun You, who was 12 years old then, sensed that something was wrong. He told his uncle Xun Qu, "This man looks suspicious. I believe he's up to something." Upon investigation, it was revealed that Zhang Quan was actually a murderer on the run. Because of this incident, the young Xun You was seen as an extraordinary boy.(攸少孤。及曇卒，故吏張權求守曇墓。攸年十三，疑之，謂叔父衢曰：「此吏有非常之色，殆將有姦！」衢寤，乃推問，果殺人亡命。由是異之。) Sanguozhi vol. 10. When Xun You was six or seven, Xun Qu once accidentally injured him while he was drunk. Since then, every time Xun You left or entered his home, he would do so at times to deliberately avoid meeting his uncle. Xun Qu was very surprised by his nephew's intelligence when he heard about it.(魏書曰：攸年七八歲，衢曾醉，誤傷攸耳；而攸出入遊戲，常避護不欲令衢見。衢後聞之，乃驚其夙智如此。) Wei Shu annotation in Sanguozhi vol. 10.
Early career 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).(南陽陰脩為潁川太守，以旌賢擢俊為務，舉五官掾張仲方正，察功曹鍾繇、主簿荀彧、主記掾張禮、賊曹掾杜祐、孝廉荀攸、計吏郭圖為吏，以光國朝) Hanshu (by Xie Cheng) annotation in Sanguozhi, vol.13. He was appointed as a Gentleman of the Yellow Gate (), allowing him to act as a liaison to the palace, in the imperial capital, Luoyang and would be the person fellow recruit Zheng Tai would complain to . However, within the same year, He Jin was assassinated by the eunuch faction he had sought to destroy. The warlord Dong Zhuo took advantage of the ensuing political turmoil to hijack and control the central government. Between 190 and 191, several regional warlords formed a coalition and launched a campaign against Dong Zhuo in the name of saving the emperor, in response Dong Zhuo ordered Luoyang to be burnt down and relocated the capital to Chang'an. In Chang'an, Xun You secretly plotted with Zheng Tai (), He Yong, Chong Ji () and Wu Qiong () to assassinate Dong Zhuo, who was notorious for his cruelty and tyranny. However, they were discovered and Xun You was arrested and imprisoned. While he was incarcerated, Xun You spoke and behaved normally as though nothing had happened. He was only released after Dong Zhuo was killed in 192.(何進秉政，徵海內名士攸等二十餘人。攸到，拜黃門侍郎。董卓之亂，關東兵起，卓徙都長安。攸與議郎鄭泰、何顒、侍中种輯、越騎校尉伍瓊等謀曰：「董卓無道，甚於桀紂，天下皆怨之，雖資彊兵，實一匹夫耳。今直刺殺之以謝百姓，然後據殽、函，輔王命，以號令天下，此桓文之舉也。」事垂就而覺，收顒、攸繫獄，顒憂懼自殺，攸言語飲食自若，會卓死得免。) Sanguozhi vol. 10. However, the Wei Shu mentioned that Xun You was released after he sent someone to persuade and convince Dong Zhuo to free him.(魏書云攸使人說卓得免，與此不同。) Wei Shu annotation in Sanguozhi vol. 10.
Xun You then resigned amidst the chaos resulting from Dong Zhuo's assassination and fled home. Appointed to be the Chancellor () of Rencheng State (任城; southwest of present-day Zoucheng, Shandong), he rejected this appointment and asked to be the Administrator () 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. However, he was unable to travel to Shu Commandery as the routes to Shu had been cut off in the chaos, choosing instead to stay in the relative stability of Jing Province.(棄官歸，復辟公府，舉高第，遷任城相，不行。攸以蜀漢險固，人民殷盛，乃求為蜀郡太守，道絕不得至，駐荊州。) Sanguozhi vol. 10.
Service under Cao Cao In 196,Zizhi Tongjian vol. 62. the warlord Cao Cao took control of Emperor Xian and brought him to Xu (許; present-day Xuchang, Henan), establishing the new capital there. He wrote to Xun You: "The Empire is in chaos. It is time for intelligent people to do something. Do you not think you have spent too much time observing the changes in the Shu region?" Xun You was then appointed as the Administrator () of Runan Commandery (汝南郡; around present-day Gushi County, Henan) and later, probably in 198,Sanguozhi vol.1. When Cao Cao installed the rank of Master of the Army summoned to the capital to serve as a Master of Writing (). Cao Cao had long heard of Xun You and was overjoyed when they finally met. He told Xun Yu and Zhong Yao: "Gongda is no ordinary person. Now that I have him to advise me, why should I worry about not being able to pacify the Empire?" He also appointed Xun You as Master of the Army (),(太祖迎天子都許，遺攸書曰：「方今天下大亂，智士勞心之時也，而顧觀變蜀漢，不已乆乎！」於是徵攸為汝南太守，入為尚書。太祖素聞攸名，與語大恱，謂荀彧，鍾繇曰：「公達，非常人也，吾得與之計事，天下當何憂哉！」以為軍師。) Sanguozhi vol. 10. always accompanying Cao Cao on campaign(自從太祖征伐，常謀謨帷幄) Sanguozhi vol.10. with Rafe De Crespigny identifying the rank as a chief of staff role, becoming one of Cao Cao's chief advisers. He would become close to Zhong Yao初，潁川荀攸、鍾繇相與親善。攸先亡，子幼。繇經紀其門戶，欲嫁其妾
Sanguozhi vol.29. and seems to have worked closely with the young Guo Jia, another chief adviser. At some unknown point he helped compile a collection of administrative and penal codes for Cao Cao called the "Wei guan yi".
Battles against Zhang Xiu and Lü Bu
In 198, when Cao Cao wanted to launch another attack on a rival warlord, Zhang Xiu, Xun You advised against it, saying, "Zhang Xiu and Liu Biao share borders. Zhang Xiu and his wandering army rely on Liu Biao for supplies. Liu Biao is unable to provide for them so they will eventually fall out. Why not wait and try to induce Zhang Xiu to surrender to you? When Zhang Xiu ends up in a desperate situation, Liu Biao will definitely support him." Cao Cao ignored Xun You's advice and attacked Zhang Xiu at Rang County (穰縣; present-day Dengzhou, Henan). Just as Xun You predicted, Liu Biao sent reinforcements to help Zhang Xiu, threatening Cao Cao's rear so putting Cao Cao's attacking forces in a disadvantageous position. Cao Cao told Xun You that he regretted not listening to his advice and was forced to retreat with mixed results against his pursuers.(建安三年，從征張繡。攸言於太祖曰：「繡與劉表相恃為彊，然繡以遊軍仰食於表，表不能供也，勢必離。不如緩軍以待之，可誘而致也；若急之，其勢必相救。」太祖不從，遂進軍之穰，與戰。繡急，表果救之。軍不利。太祖謂攸曰：「不用君言至是。」乃設奇兵復戰，大破之。) Sanguozhi vol. 10.
Despite the setback Cao Cao wanted to move to attack another rival warlord, the warrior Lü Bu in Xu Province to the east. Some warned against moving east as Zhang Xiu and Liu Biao might attack after their recent victory. However, Xun You had a different opinion: he believed that Zhang Xiu and Liu Biao had yet to recover from a heavy defeat when pursuing Cao Cao and would not make any further moves. He warned Lü Bu was a formidable warrior and had support from the claimant emperor Yuan Shu, if left unchecked he could become a considerable threat and many would support him but right now, Lü Bu's allied forces were not yet organized so could be defeated if they moved now. Lü Bu defeated Liu Bei and received help from Zang Ba but his uncoordinated army would struggle against Cao Cao.(魏書曰：議者云表、繡在後而還襲呂布，其危必也。攸以為表、繡新破，勢不敢動。布驍猛，又恃袁術，若從橫淮、泗間，豪傑必應之。今乘其初叛，衆心未一，往可破也。太祖曰：「善。」比行，布以敗劉備，而臧霸等應之。) Wei Shu annotation in Sanguozhi vol. 10.