city and capital of Shanxi (Shansi) sheng (province), China. One of the greatest industrial cities in China, it lies on the Fen River in the northern portion of the river's fertile upper basin. Taiyuan commands the north-south route through Shanxi, as well as important natural lines of communication through the mountains to Hebei province in the east and, via Fenyang, to northern Shaanxi (Shensi) province in the west. Pop. (2002 est.) city, 1,970,304; (2007 est.) urban agglom., 2,913,000.

The city was originally the site of Jinyang, a strategic centre for the ancient states of Jin and Zhao. After the Qin (Qin dynasty) conquest of Zhao and other states in 221 BCE, it became the seat of the commandery (district under the control of a commander) of Taiyuan, which continued during the Han dynasty (206 BCE–220 CE) and after. In the Dong (Eastern) Han period (25–220 CE), it became the capital of the province (zhou) of Bing. In the 6th century it was for a time a secondary capital of the Dong Wei and Bei (Northern) Qi states, growing into a large city and also becoming a centre of Buddhism. From that time until the middle of the Tang dynasty (618–907), the construction of the cave temples at Tianlong Mountain, southwest of the city, continued. The dynastic founder of the Tang began his conquest of the empire with Taiyuan as a base and using the support of its local aristocracy. It was periodically designated as the Tang's northern capital and grew into a heavily fortified military base.

The Song (Song dynasty) reunified China in 960, but Taiyuan continued to resist, and it was destroyed during fighting in 979. A new city was set up on the banks of the Fen in 982, a short distance from the old site. The city became a superior prefecture in 1059 and the administrative capital of Hedong (northern Shanxi) in 1107. It retained this function, with various changes in its name and status, until the end of the Yuan (Yuan dynasty) (Mongol) period (1368). At the beginning of the Ming dynasty (1368–1644), it was renamed Taiyuan Fu (fu meaning “chief town”); it retained this name until 1912. During the Ming and Qing (Qing dynasty) (1644–1911/12) periods, it was the capital of Shanxi. Under the republic (established in 1911), its name was changed to Yangqu, which it retained until 1927.

In 1907 the importance of Taiyuan was increased by the construction of a rail link to Shijiazhuang (in Hebei province), on the Beijing-to- Wuhan trunk line. Soon thereafter Taiyuan suffered a serious economic crisis. In the 19th century the merchants and local banks of Shanxi had been of national importance, but the rise of modern banks and the Taiping Rebellion (1850–64) led to the rapid decline of this system—with disastrous effects upon Shanxi and its capital.

After 1911 Shanxi remained under a powerful warlord, Yan Xishan, who retained control from 1913 to 1948. Taiyuan flourished as the centre of his comparatively progressive province, and the city experienced extensive industrial development. It was linked by rail both to the far southwest of Shanxi and to Datong in the north.

After the Japanese invasion in 1937, Taiyuan's industries developed still further. In 1945 the Japanese army in Shanxi surrendered to Yan Xishan, and it continued to fight for him until 1948. Eventually, the Chinese communist armies captured Taiyuan, but only after a destructive battle.

Since 1949 Taiyuan's industrial growth has been dramatic, and the city proper now covers an area a dozen times larger than what it was in the 1950s. Several industrial districts have been established on the outskirts of the city (particularly in the northern and western suburbs), including those with iron- and steelmaking works, engineering and machine-making shops, and large chemical-industrial complexes. Local coal production is considerable and has been used in large thermal-power-generating operations, although this activity also has produced heavy air pollution in the region. Taiyuan's role as a regional communication centre has been further strengthened by the construction of rail lines to Henan and southern Hebei provinces and expressways east to Shijiazhuang, north to Datong, and south to Yuncheng. The city's airport provides domestic and international flight services to a variety of destinations.

In addition to its position as an industrial giant, Taiyuan is also a centre of education and research, particularly in technology and applied science. Notable schools include Shanxi University (1902) and Taiyuan University of Technology, which originally was part of Shanxi University and became a separate institution in 1953. Jin Memorial Hall, a famous ancient structure 15 miles (25 km) southwest of the city, is under state protection and is a popular tourist attraction.