Cao Wei
Cao Wei (220–265) 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. Historians often add the prefix "Cao" to distinguish it from other Chinese states known as "", such as Wei of the Warring States period and Northern Wei of the Southern and Northern Dynasties. The authority of the ruling Cao family gradually weakened after the death of the second Wei emperor, Cao Rui, and eventually fell into the hands of Sima Yi, a Wei regent, and his family, in 249. Cao Rui's successors remained as puppet rulers under the control of the Simas until Sima Yi's grandson, Sima Yan, forced the last Wei ruler, Cao Huan, to abdicate the throne and established the Jin dynasty.
Towards the end of the Eastern Han dynasty, northern China came under the control of Cao Cao, the chancellor to the last Han ruler, Emperor Xian. In 213, Emperor Xian granted Cao Cao the title of "Duke of Wei" (魏公) and gave him ten cities as his dukedom. The area was named "Wei". At that time, the southern part of China was divided into two areas controlled by two other warlords, Liu Bei and Sun Quan. In 216, Emperor Xian promoted Cao Cao to the status of a vassal king — "King of Wei (魏王)" — and granted him more territories.
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