Death of Cao Cao and Hua Tuo

In 220, Cao Cao died in Luoyang due to an unrecorded illness. Legends had many explanations for the cause of his death, most of which were wrought with superstitions. The Romance of the Three Kingdoms included some of these legends, as well as Luo Guanzhong's own story about the involvement of Hua Tuo, a renowned Chinese physician.

When Cao Cao started complaining about splitting headaches during the last days of his life, his subjects recommended Hua Tuo, a physician whose skills were said to parallel the deities. Upon examination, Hua Tuo diagnosed Cao Cao's illness to be a type of rheumatism within the skull. He suggested giving Cao Cao a dose of hashish and then splitting open his skull with a sharp axe to extract the pus within.

However, due to an earlier incident with another physician who attempted to take Cao Cao's life, Cao Cao grew very suspicious of any physician, as Cao Cao was the target of many plots against his life, including one by Dong Cheng, a relative of the Emperor. Cao Cao believed Hua Tuo intended to kill him to avenge the death of Guan Yu. He then threw Hua Tuo into jail, where the renowned physician died a few days later. Without proper treatment, Cao Cao soon died as well. Some believed his death to be the result of a curse that befell when he tried to cut down a sacred tree