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Emperor Xiaowu, last emperor of the proto-mongolic Xiangbei led Northern Wei. He is at times known as Emperor Chu (出帝, "the emperor who fled").
After the general Gao Huan rebelled against and defeated the clan of the deceased paramount general Erzhu Rong in 532, he made Emperor Xiaowu emperor. Despite Gao's making him emperor, however, Emperor Xiaowu tried strenuously to free himself from Gao's control, and in 534, he, aligning with the general Yuwen Tai, formally broke with Gao. When Gao advanced south to try to again take control of the imperial government, Emperor Xiaowu fled to Yuwen's territory, leading to Northern Wei's division into two (as Gao then made Yuan Shanjian (Emperor Xiaojing of Eastern Wei) the heir apparent, establishing Eastern Wei). Emperor Xiaowu's relationship with Yuwen, however, soon deteriorated over Yuwen's refusal to condone his incestuous relationships with his cousins, and around the new year 535, Yuwen poisoned him to death. Emperor Xiaowu's successor, Yuan Baoju (Emperor Wen of Western Wei), is typically regarded, then, as the first emperor of Western Wei, formalizing the division of the empire.
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