Outer Manchuria
The original inhabitants of the region were apparently the Mohe and other Tungusic tribes. Other entities occupying parts of Outer Manchuria include the ancient mixed Mohe and proto-Korean kingdoms of Goguryeo and Balhae, whose territories extended from the northern Korean peninsula to the southern and central parts of Inner and Outer Manchuria. According to the Treaty of Nerchinsk in 1689, the Manchu-Russian border was the Argun River and the Stanovoy Mountains until the Pacific coast. The eastern end of the boundary was generally held to be the Uda River, leaving Outer Manchuria to China. However, the Qing dynasty ceded Outer Manchuria to Russia in the Treaty of Aigun in 1858 and the Treaty of Peking in 1860. A small region to the north of the Amur, known as the Sixty-Four Villages East of the (Heilongjiang) River, was kept by the Qing dynasty under the Treaty of Aigun, but was invaded and annexed by Russia in 1900. Outer Manchuria formed part of the far eastern provinces of the Soviet Union and was used as the launch-pad for the Soviet assault on Japanese-occupied Inner Manchuria in 1945. During the Chinese Civil War, Chinese communist forces began the war with large amounts of Inner Manchuria already in their hands; in 1949, the victorious communists established the present-day People's Republic of China.