History of Bayannur
The Zhao Dynasty (403 BCE–222 BCE) controlled an area including modern-day Bayannur, while the Western Han Dynasty (206 BCE–24 CE) established a hierarchical Chinese administrative structure. The Qing Dynasty (1644–1912) designated this area as part of “Inner Mongolia”, but after its overthrow by the Republic of China (1912-1949), Bayannur was assigned to Suiyuan Province. Because of Mongol-Chinese cooperation with the Communist faction in the Chinese Civil War (stalled since 1950), Suiyuan was annexed to the new Inner Mongolia Autonomous Region from 1954, although not without controversy because of the province’s large and longstanding ethnic Han majority.
Source From: https://en.wikipedia.org/wiki/Bayannur#History