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. Described as a highly profound and insightful thinker, Xun You was also known for keeping a very low profile and hiding his true talents and achievements behind the façade of a foolish, cowardly and weak person.