Who they were
A warlord, statesman and poet of the late Han, Cao Cao rose fighting the Yellow Turbans. From 196 he held custody of Emperor Xian, “commanding the lords in the emperor’s name.”
What they did
He unified the north by defeating Yuan Shao at Guandu (200), but his southward drive was stopped at Red Cliffs (208). King of Wei from 216, he never took the imperial throne; his son Cao Pi founded the Wei dynasty in 220 and honored him posthumously as Emperor Wu of Wei. His innovations included promotion by talent over birth and military agricultural colonies (tuntian) that fed his armies. He was also a fine poet — the “Short Song” is a classic.
Legacy
The Romance of the Three Kingdoms cast Cao Cao as the brilliant villain; modern assessments emphasize his statesmanship and literary gifts.