Wei (220–266), also known as Cao Wei, was one of the three major states that competed for supremacy over China in the Three Kingdoms period (220–280). With its capital at Luoyang, the state was established by Cao Pi in 220, based upon the foundations laid by his father, Cao Cao, towards the end of the Eastern Han dynasty. The name "Wei" first became associated with Cao Cao when he was named the Duke of Wei by the Eastern Han government in 213, and became the name of the state when Cao Pi proclaimed himself emperor in 220. ——Wikipedia  @en