Cao Pi forced Emperor Xian of Han to cede the throne to him, and founded the state of Wei.
Tips
mistakes
Here 禅 reads shàn, "to hand over the throne", not chán as in 禅宗 "Zen Buddhism". The two readings are unrelated words that share one character.
history
Confucians held up the legendary handovers from 尧 to 舜 and from Shun to 禹 as the ideal: the throne went to the worthiest man, not to a son. Later usurpers staged formal abdications to make a seizure of power look legitimate, as 曹丕 did in 220.