Tongliao[a] is a prefecture-level city in eastern Inner Mongolia, People's Republic of China. The area is 59,535 square kilometres (22,987 sq mi) and as of the 2020 census, its population was 2,873,168 (3,139,153 in 2010). However, the city proper made of Horqin district, had 921,808 inhabitants.[3] The city was the administrative centre of the defunct Jirem League.[b] The original Mongolian name for Tongliao city proper (i.e. Horqin District) is Bayisingtu (Chinese: 白音泰赉; pinyin: Báiyīntàilài; lit. 'having buildings'), while the original name of the prefecture-level city is Jirem. The Mongolian dialect spoken in this area is Khorchin Mongolian. Human settlement in Tongliao and the surrounding Khorchin area dates from at least 1000 BC. The Donghu people, a tribe who spoke a proto-Mongolian language, settled in today's Tongliao area, north of Yan during the Warring States period.[5] their culture was associated with the Upper Xiajiadian culture, characterized by the practice of agriculture and animal husbandry supplemented by handicrafts and bronze art.[6] Later, the Tongliao area was controlled by Xiongnu, Xianbei, and Khitan tribes.