Cao Cao was born in Qiao of the State of Pei (today's Boxian County, AnhuiProvince). While he was still a young man, he demonstrated his intelligence and talent. Cao Cao's political career began when he was commissioned as a military officer to fight the Yellow Scarf Rebels in Yingchuan. Military success soon elevated him to the position of chancellor to the prince of Jinan. He returned to Luoyang, the capital city, a few years later when the imperial government assigned him to a new post. When a scramble for power within the royal court created major confusion in the capital, a warlord named Dong Zhuo was sent for to clean up the mess.
In reality Dong Zhuo was coming back to grab power. He offered Cao Cao a promotion in exchange for working with him. Cao Cao, whose political abilities were becoming better appreciated, declined the offer, seeing that Dong Zhuo's cruelty and folly as a politician would soon bring destruction down on him. Instead, Cao Cao stole out of the capital and traveled to Chenliu to join his father, who invested his entire fortune in his son's campaign against Dong Zhuo.
With a local tycoon and his cousin Cao Hong donating funds and personnel respectively, in addition to his father's support, Cao Cao built up an army of 5,000, which he put into training while he kept an eye on the political dynamics of a restive empire. Uprisings across the country had furnished local authorities with a perfect excuse to increase their weaponry.
After Dong Zhuo had dethroned the emperor and killed him, then manipulated the coronation of another son from the royal family. Local governments all started to be roused in indignation, while at the same time secretly looking for possible ways to slip into the power vacuum left by a weakened central government. Of all the local warlords standing up against Dong Zhuo, Yuan Shao was the greatest and most admired. Son of an eminent family, Yuan Shao was the governor of Bohai Prefecture when he built up his own army against Dong Zhuo, whom he had battled with while in the capital Luoyang.