Mianyang is the second largest prefecture-level city of Sichuan Province in Southwest China. Its administrative area includes the city proper of Mianyang, with 985,586 inhabitants in the built up area (2 urban counties), the county-level city of Jiangyou, and six counties, covering an area of over 20,281 square kilometers (7,831 sq mi) and a population of 4,613,862 at the 2010 census. Mianyang, called Fujun in ancient times, had advanced in agriculture during the Qin (221-206 BC) and Han (206 BC-220 AD) dynasties. It has a history of over 2,200 years since the Emperor Gaozu of Han established the first county in this area in 201 BC. Due to its advantageous geographic location, it had always been a town of great military importance and formed a natural defense for Chengdu.