and was subsequently absorbed by the Song dynasty (960–1126) in 1081. The name Lanzhou was reestablished, and the county renamed Lanzhuan. After 1127 it fell into the hands of the Jin dynasty, and after 1235 it came into the possession of the Mongol Empire. Under the Ming dynasty (1368–1644) the prefecture was demoted to a county and placed under the administration of Lintao superior prefecture, but in 1477 Lanzhou was reestablished as a political unit. The city acquired its current name in 1656, during the Qing dynasty. When Gansu was made a separate province in 1666, Lanzhou became its capital. In 1739 the seat of Lintao was transferred to Lanzhou, which was later made a superior prefecture called Lanzhou. Lanzhou was badly damaged during the Dungan revolt in 1864–1875. In the 1920s and 1930s it became a center of Soviet influence in northwestern China. Second Sino-Japanese War-World War II During the Second Sino-Japanese War (1937–1945) Lanzhou, linked with Xi'an by highway in 1935, became the terminus of the Chinese–Soviet highway, used as a route for Soviet supplies destined for the Xi'an area. This highway remained the primary traffic route of northwestern China until the completion of the railway from Lanzhou to Ürümqi, Xinjiang. The Battle of Lanzhou Lanzhou's old Donggang Airport, located near the city centre, was the primary entry point for combat aircraft provided to China under the Sino-Soviet Non-Aggression Pact, and along with other targets around Lanzhou, including civilian centers, were heavily bombed by the Imperial Japanese Army Air Force and Navy Air Force. Many air battles were fought between the Chinese Air Force and the Imperial Japanese air forces over Lanzhou and surrounding regions from 1937 to 1945, particularly from 1938 to 1941 when the influx of Soviet war materials formed the primary support in China's War of Resistance against the Imperial Japanese invasion. Instances of major air-battles include an IJAAF raid consisting of 30 BR.20 and Ki-21 bombers against civilian targets in Lanzhou on 20 February 1939; 17th PS, 5th PG commander Capt. Cen Zeliu and his deputy commander Capt. Ma Guolian (Ma Kwok-Lim), a Canadian-Chinese volunteer for the Chinese Air Force, shot down the first two bombers in the battle, followed by two more downed as Capt. Cen led another attack on the third formation. They would be joined by pilots of the Soviet Volunteer Group led by Nikolay Garilov and the 15th PS led