Tonghua, Wade-Giles romanization T’ung-hua, city, southwestern Jilin sheng (province), northeastern China. It is situated in the valley of the Hun River in the densely forested Changbai Mountains—an area well known from early times for the manufacture of various forest products and for ginseng (a medicinal preparation made from an aromatic root).
The region was for some time considered an originating place of the Manchu, who kept a Manchu preserve during the Qing (Manchu) period (1644–1911/12). It was officially opened for Han Chinese settlement in 1877, and a county named Tonghua was set up there the same year. Most of the first settlers came from Shandong province, many of them during and after the great famines of the 1870s. During the early period, most of Tonghua’s trade went via the Hun and Yalu rivers, but under the Japanese occupation of Manchuria (Northeast China) after 1932, a railway was constructed linking Tonghua with the main Manchurian rail network and with northern Korea. The area was found to be rich in coal and iron ore. The Japanese planned to establish a base of heavy industry there and constructed a power station on the Hun River. Iron ore from the area was sent to the great steelworks at Anshan in Liaoning province.
Since 1949 Tonghua has changed from a centre of light manufacturing, producing vegetable oils, wines, and various handicrafts, to a heavily industrialized city. A large paper industry has been set up, and engineering plants making such products as electrical and power equipment and mining machinery have been established. The most important development, however, has been the construction of a large integrated iron and steel complex. Coal is mined in the area. Other manufactures include building materials, pharmaceuticals, and textiles; quality wines made in Tonghua are acclaimed throughout China. Some 30 miles (50 km) southeast of the city are the sites of the capital cities and tombs of the ancient Koguryo kingdom, collectively designated a UNESCO World Heritage site in 2004. Pop. (2002 est.) 392,845.