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The original name of Datong County in Shanxi Province was Yunzhong County, which was occupied by the Tang Dynasty during the fifth generation. It was ceded to the Chitan Country by Shi Jingtang in 936 A.D., and from then on, the name was changed to Xidan.

During the Magnificent Tang Dynasty, Da Tong Prefecture was a road that had to be passed from Chang'an to the outer northern regions