Liaoning, province, located in Northeast China, occupying the southern part of the historic region of Manchuria. It is bordered on the south by inlets of the Yellow Sea and on the southeast by the Yalu River (its border with North Korea). The province comprises a central plain traversed by the Liao River, bordered on the east by the generally hilly Liaodong Peninsula and on the west by a complex of low hills. Liaoning is China's most urbanized and industrialized province. Dalian, the major port of northeastern China, and the capital, Shenyang, are large industrial centers; other leading cities include Anshan, Fuxin, Fushun, and Jinzhou. Liaoning first became part of China in the Han dynasty (206 bc-ad 220) and was reincorporated in the Tang (T’ang) dynasty (618-907). From the 10th to the 13th century it formed part of the non-Chinese Liao and Jin empires and was again part of China under the Qing (Manchu) emperors (1644-1911). The Liaodong Peninsula was held by Russia from 1896 to 1905. In 1905 the peninsula passed to Japan, the entire province being taken by the Japanese in 1931; it was made a part (1932-1945) of the Japanese-controlled state of Manchukuo. The province's modern industrial base was established during the Japanese occupation. Area, 151,000 sq km (58,301 sq mi); population 27,037,000 (2003 estimate).