or Lü-shun formerly Port Arthur
Former city, since 1950 a district of Dalian city, Liaoning province, northeastern China.
Situated at the southern tip of the Liaodong Peninsula , it was used as a staging post as early as the 2nd century BC. Fortified under the Ming dynasty , it was captured by the Manchu s in 1633 and served as the seat of a defense unit under the Qing dynasty . In 1878 it became the chief base for China's first modern naval force. Leased to Russia in 1898, it was captured by Japan (1905) during the Russo-Japanese War and was made the seat of a provincial government. Under a 1945 treaty it became a Sino-Soviet military base; the Soviet forces withdrew in 1955.