>>8216697Beijing first became the capital under the Liao dynasty founded by Khitan who were ruled by the Tang dynasty preceding them. Next Beijing became the capital of the Jin dynasty. Beijing wasn't sacked by either the Liao or Khitan. the Mongols sacked and raped Zhongdu (Beijing) when it was a Jurchen majority city. no Han capital got sacked, but Hanoi was sacked and raped by the Mongols. The Southern Song capital at Hangzhou (Lin'an) wasn't sacked. The Han Chinese Southern Song child Emperor Gong (Zhao Xian) just captiulated in Hangzhou and married a Mongol princess while Mongols raped Vietnamese women in Hanoi. The Chinese Tran emperors left their seed all over Vietnam.
The Heishui Mohe (Jurchens), Shiwei (Mongols) and Khitan were all ruled by Han Chinese in the Tang dynasty before the Liao, Jin and Yuan.
Beijing was the provisional capital of An Lushan's Yan dynasty but the only sacking and raping there was Gao Juren raping and sacking An Lushan's people in that city after defeating his rebellion specifically hunting for barbarians with An Lushan's facial features.
The very names of the Liao, Yuan and Qing dynasties derive from Chinese and none of them are valid words in the Khitan, Mongol and Manchu languages.